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Witassek F, Radovanovic D, Rickli H, Pedrazzini G, Erne P, Muller O, Eberli FR, Roffi M. P4391Cardiovascular risk factor trends over two decades in patients presenting with acute myocardial infarction: a failure of smoking control, especially in women. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Hypertension, diabetes, dyslipidemia and smoking are established cardiovascular risk factors (CVRF). Little is known about the changes of risk factor profiles over time in patients presenting with acute myocardial infarction (AMI).
Purpose
To analyze the temporal trends of CVRF in patients presenting with AMI over the last 22 years in Switzerland.
Methods
We included data of all AMI patients enrolled between 1997 and 2018 in the Swiss nationwide AMIS Plus registry. The rates of hypertension, diabetes, dyslipidemia and smoking at presentation were descriptively analyzed dividing the data into 2-year periods. Trend analyses were performed using the CHI-square-test and ANOVA. A p-value of <0.005 was considered as statistically significant.
Results
A total of 57,995 patients were included in the analysis (73.6% male). The mean age was 66.0 years (males: 64.0 years, females 71.6 years) and did not differ over the study period. The mean CVRF rates over the study period were as follows: diabetes 20.5% (males: 19.4%, females: 23.6%), hypertension 60.2% (males: 57.0%, females: 69.0%), dyslipidemia 59.4% (males: 60.5%, females: 56.4%), and smoking 39.3% (males: 43.0%, females: 28.7%). While there was no significant change over time in the rates of diabetes for both genders, there were significant increases in the rates of hypertension and dyslipidemia for both males and females (p<0.001 for all comparisons). In terms of smoking, there was no significant trend for males while there was a significant increase in the rate of smoking for females (p<0.001). As a result, the gap in smoking rates between men and women decreased from 19.9% (45.3% vs. 25.4%) in 1997/98 to 7.9% (41.2% vs. 33.3%) in 2017/18.
Trends in the rate of smokers
Conclusions
Among patients presenting with AMI in Switzerland over two decades, the prevalence of hypertension and dyslipidemia increased in both men and women, while diabetes at presentation did not change over the years. We documented a failure of smoking control, with a lack of a reduction in the smoking prevalence among males and a striking increase among women.
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Affiliation(s)
- F Witassek
- University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, Zurich, Switzerland
| | - D Radovanovic
- University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, Zurich, Switzerland
| | - H Rickli
- Cantonal Hospital St. Gallen, Department of Cardiology, St. Gallen, Switzerland
| | - G Pedrazzini
- Cardiocentro Ticino, Division of Cardiology, Lugano, Switzerland
| | - P Erne
- University of Zurich, AMIS Plus Data Center, Epidemiology, Biostatistics and Prevention Institute, Zurich, Switzerland
| | - O Muller
- University Hospital Centre Vaudois (CHUV), Department of Cardiology, Lausanne, Switzerland
| | - F R Eberli
- Triemli Hospital, Department of Cardiology, Zurich, Switzerland
| | - M Roffi
- Geneva University Hospitals, Division of Cardiology, Geneva, Switzerland
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Meyer MR, Kurz DJ, Radovanovic D, Pedrazzini G, Roffi M, Rosemann T, Eberli FR. P5564Differences in presentation and clinical outcomes between patients with acute myocardial infarction and right or left bundle branch block. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p5564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- M R Meyer
- Triemli Hospital, Division of Cardiology, Department of Internal Medicine, Zürich, Switzerland
| | - D J Kurz
- Triemli Hospital, Division of Cardiology, Department of Internal Medicine, Zürich, Switzerland
| | - D Radovanovic
- University of Zurich, AMIS Plus Data Center, Zurich, Switzerland
| | - G Pedrazzini
- Cardiocentro Ticino, Department of Cardiology, Lugano, Switzerland
| | - M Roffi
- Geneva University Hospitals, Division of Cardiology, Geneva, Switzerland
| | - T Rosemann
- University of Zurich, Institute of Primary Care, Zurich, Switzerland
| | - F R Eberli
- Triemli Hospital, Division of Cardiology, Department of Internal Medicine, Zürich, Switzerland
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Eberli FR. Quality improvement in the treatment of acute coronary syndrome patients. Swiss Med Wkly 2016; 146:w14302. [DOI: 10.4414/smw.2016.14302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Zbinden R, Von Felten S, Tueller D, Kurz DJ, Reho I, Galatius S, Alber H, Pfisterer M, Kaiser C, Eberli FR. Impact of stent diameter and length on in-stent restenosis after drug eluting stent versus bare metal stent implantation in patients needing large coronary stents. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.1046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Roffi M, Radovanovic D, Erne P, Urban P, Windecker S, Eberli FR. Gender-related mortality trends among diabetic patients with STEMI: insights from a nationwide registry 1997- 2010. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht307.p441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Radovanovic D, Seifert B, Urban P, Eberli FR, Rickli H, Bertel O, Erne P. Charlson Comorbidity Index in patients hospitalized with acute coronary syndrome. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht309.p3122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Cook S, Eshtehardi P, Kalesan B, Raber L, Wenaweser P, Togni M, Moschovitis A, Vogel R, Seiler C, Eberli FR, Luscher T, Meier B, Juni P, Windecker S. Impact of incomplete stent apposition on long-term clinical outcome after drug-eluting stent implantation. Eur Heart J 2012; 33:1334-43. [DOI: 10.1093/eurheartj/ehr484] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Billinger M, Beutler J, Taghetchian KR, Remondino A, Wenaweser P, Cook S, Togni M, Seiler C, Stettler C, Eberli FR, Luscher TF, Wandel S, Juni P, Meier B, Windecker S. Two-year clinical outcome after implantation of sirolimus-eluting and paclitaxel-eluting stents in diabetic patients. Eur Heart J 2008; 29:718-25. [DOI: 10.1093/eurheartj/ehn021] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Cuculi F, Radovanovic D, Eberli FR, Stauffer JC, Bertel O, Erne P. The Impact of Statin Treatment on Presentation Mode and Early Outcomes in Acute Coronary Syndromes. Cardiology 2007; 109:156-62. [PMID: 17726316 DOI: 10.1159/000106676] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Accepted: 12/25/2006] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The role of statin use in the treatment of acute coronary syndromes (ACS) is not clear. The aim of our study was to evaluate the role of statins in ACS. METHODS Using data from the Acute Myocardial Infarction in Switzerland (AMIS Plus) Project, we compared the effects of chronic statin use, statin therapy after admission and no statin therapy on presentation mode and outcomes in ACS. RESULTS Available data from the period 2001-2006 including 11,603 patients were analyzed. Major cardiac event rates and in-hospital mortality were more common in statin-naive patients compared to patients who received statins. CONCLUSIONS Our results support the importance of statin treatment in ACS. Chronic statin therapy seems to alter the initial presentation of ACS but it is questionable whether it provides an additional effect on early outcomes compared to the establishment of statin therapy after admission in statin-naive patients.
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Affiliation(s)
- F Cuculi
- Department of Cardiology, Kantonsspital Luzern, Luzern, Switzerland
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Roffi M, Baumgartner RW, Eberli FR. No reflow during carotid stenting. Heart 2005; 92:538. [PMID: 16537773 PMCID: PMC1860852 DOI: 10.1136/hrt.2005.070896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Brunschwig T, Eberli FR, Herren T. [Mechanical complications of acute myocardial infarction]. Z Kardiol 2004; 93:897-907. [PMID: 15568150 DOI: 10.1007/s00392-004-0133-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2004] [Accepted: 06/21/2004] [Indexed: 05/01/2023]
Abstract
Rupture of the left ventricular myocardium during the course of an acute myocardial infarction may affect the free wall, the interventricular septum, or the papillary muscles. When a rupture occurs, it is referred to as a mechanical complication of acute myocardial infarction. All mechanical complications may lead to cardiogenic shock. However, the location of the rupture can often be suspected clinically. To confirm the diagnosis, echocardiography must be performed. Since the advent of thrombolytic therapy and percutaneous coronary intervention, the incidence of mechanical complications has declined. Even though mortality remains high, their recognition is important since survivors may have an excellent long-term prognosis. The cases convey two main messages: 1) Mechanical complications must be carefully searched for in any patient with an acute coronary syndrome and signs of cardiogenic shock and/or a systolic murmur. 2) Aggressive and timely medical and surgical treatment should be provided even though in a substantial proportion of these patients prognosis may be dismal.
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Affiliation(s)
- T Brunschwig
- Medizinische Klinik, Spital Limmattal, Urdorferstrasse 100, 8952 Schlieren, Schweiz
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Largiadèr T, Eberli FR. [Valve disease: what the general practicioner needs to know]. Praxis (Bern 1994) 2004; 93:1539-1547. [PMID: 15495767 DOI: 10.1024/0369-8394.93.38.1539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Patients with mitral or aortic valve disease constitute an important part of patients in cardiology practice. General practitioners and internists have an important role in the long-term care of these patients. We review current knowledge and recommendations for follow-up, medical therapy and indications for surgery in patients with aortic and mitral valve disease. Asymptomatic patients with valve disease need a clinical and echocardiographic follow-up at specific time intervals. Most patients with mild or moderate valve disease do not need medical or surgical therapy. However, once a patient becomes symptomatic, he needs a non-invasive and likely an invasive evaluation for surgical valve repair or replacement. In case the valve disease progresses without the development of clinical symptoms, the indication for surgery must be derived from hemodynamic parameters, the onset of arrhythmias (atrial fibrillation), and pulmonary hypertension. In symptomatic and asymptomatic severe valve disease specific medical therapy can be very beneficial. However, improvement under medical therapy should not delay a prognostically necessary surgical valve repair or replacement.
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Affiliation(s)
- Th Largiadèr
- Herz-Kreislauf-Zentrum, Kardiologie, Universitätsspital, Zürich
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13
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Wahl A, Eberli FR, Thomson DA, Luginbühl M. Coronary artery spasm and non-Q-wave myocardial infarction following intravenous ephedrine in two healthy women under spinal anaesthesia. Br J Anaesth 2002; 89:519-23. [PMID: 12402737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
Abstract
Vasovagal episodes occur frequently in young healthy patients undergoing venous cannulation and loco-regional anaesthesia. We report two cases of severe coronary vasospasm and non-Q-wave infarction in healthy young women after administration of ephedrine for vasovagal symptoms at the onset of spinal anaesthesia. In the light of unopposed vagal predominance pre-disposing patients to coronary vasospasm, even in young healthy patients, atrophine and not ephedrine should be the first line treatment for bradycardia with or without hypotension under spinal anaesthesia.
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Affiliation(s)
- A Wahl
- Swiss Cardiovascular Centre, University Hospital of Bern, CH-3010 Bern, Switzerland
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14
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15
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Roffi M, Eberli FR, Wyttenbach R, Gallino A. Percutaneous coronary intervention of the left main trunk in congenitally anomalous single coronary artery. J Invasive Cardiol 2001; 13:808-9. [PMID: 11731695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Anomalous origin of the coronary arteries is infrequent and a single coronary artery is seen even less frequently. Accordingly, few reports have described percutaneous coronary interventions in this anomaly. We report successful balloon angioplasty and stenting of a left main trunk originating from the right coronary artery.
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Affiliation(s)
- M Roffi
- Swiss Cardiovascular Center Bern, University Hospital, Freiburgstrasse, CH-3010 Bern, Switzerland
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16
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Pohl T, Seiler C, Billinger M, Herren E, Wustmann K, Mehta H, Windecker S, Eberli FR, Meier B. Frequency distribution of collateral flow and factors influencing collateral channel development. Functional collateral channel measurement in 450 patients with coronary artery disease. J Am Coll Cardiol 2001; 38:1872-8. [PMID: 11738287 DOI: 10.1016/s0735-1097(01)01675-8] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES We sought to determine the pathogenetic predictors of collateral channels in a large cohort of patients with coronary artery disease (CAD). BACKGROUND The frequency distribution of collateral flow in patients with CAD is unknown. Only small qualitative studies have investigated which factors influence the development of collateral channels. METHODS In 450 patients with one- to three-vessel CAD undergoing percutaneous transluminal coronary angioplasty (PTCA), collateral flow was measured. A collateral flow index (CFI; no unit) expressing collateral flow relative to normal anterograde flow was determined using coronary wedge pressure or Doppler measurements through sensor-tipped PTCA guide wires. Frequency distribution analysis of CFI and univariate and multivariate analyses of 32 factors, including gender, age, patient history, cardiovascular risk factors, medication and coronary angiographic data, were performed. RESULTS Two-thirds of the patients had a CFI < 0.25 and approximately 40% of patients had a CFI < 0.15, but only approximately 10% of the patients had a recruitable CFI > or =0.4. By univariate analysis, the following were predictors of CFI > or =0.25: high levels of high-density lipoprotein cholesterol, the absence of previous non-Q-wave myocardial infarction, angina pectoris during an exercise test, angiographic indicators of severe CAD and the left circumflex or right coronary artery as the collateral-receiving vessel. Percent diameter stenosis of the lesion undergoing PTCA was the only independent predictor of a high CFI. CONCLUSIONS This large clinical study of patients with CAD in whom collateral flow was quantitatively assessed reveals that two-thirds of the patients do not have enough collateral flow to prevent myocardial ischemia during coronary occlusion, and that coronary lesion severity is the only independent pathogenetic variable related to collateral flow.
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Affiliation(s)
- T Pohl
- Division of Cardiology, Swiss Cardiovascular Center of Bern, University Hospital, Bern, Switzerland
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17
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Abstract
BACKGROUND Beta-adrenergic blocking agents are the cornerstone in the treatment of coronary artery disease (CAD). The exact pathophysiologic mechanism is not clear but depends largely on the oxygen-sparing effect of the drug. Thus, the effect of metoprolol on coronary flow reserve and coronary flow velocity reserve (CFVR) was determined in patients with CAD. METHODS Coronary blood flow velocity was measured with the Doppler flow wire in 23 patients (age: 56 +/- 10) undergoing percutaneous transluminal coronary angioplasty for therapeutic reasons. Measurements were carried out at rest, after 1-min vessel occlusion (postischemic CFVR) as well as after intracoronary adenosine (pharmacologic CFVR) before and after 5 mg intravenous metoprolol. In a subgroup (n = 15), absolute flow was measured from coronary flow velocity multiplied by coronary cross-sectional area. RESULTS Rate-pressure product decreased after metoprolol from 9.1 to 8.0 x 10(3) mm Hg/min (p < 0.001). Pharmacologic CFVR was 2.1 at rest and increased after metoprolol to 2.7 (p = 0.002). Likewise, postischemic CFVR increased from 2.6 to 3.3 (p < 0.001). Postischemic CFVR was significantly higher than pharmacologic CFVR before as well as after metoprolol. Coronary vascular resistance decreased after metoprolol from 3.4 +/- 2.0 to 2.3 +/- 0.7 mm Hg x s/cm (p < 0.02). CONCLUSIONS The following conclusions were drawn from this study. Metoprolol is associated with a significant increase in postischemic and pharmacologic CFVR. However, postischemic CFVR is significantly higher than pharmacologic CFVR. The increase in CFVR by metoprolol can be explained by a reduction in vascular resistance. The increase in CFVR (= increased supply) and the reduction in oxygen consumption (= decreased demand) after metoprolol explain the beneficial effect of this beta-blocker in patients with CAD.
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Affiliation(s)
- M Billinger
- Department of Cardiology, Swiss Cardiovascular Center, Bern, Switzerland
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Schnyder G, Roffi M, Pin R, Flammer Y, Lange H, Eberli FR, Meier B, Turi ZG, Hess OM. Decreased rate of coronary restenosis after lowering of plasma homocysteine levels. N Engl J Med 2001; 345:1593-600. [PMID: 11757505 DOI: 10.1056/nejmoa011364] [Citation(s) in RCA: 324] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND We have previously demonstrated an association between elevated total plasma homocysteine levels and restenosis after percutaneous coronary angioplasty. We designed this study to evaluate the effect of lowering plasma homocysteine levels on restenosis after coronary angioplasty. METHODS A combination of folic acid (1 mg), vitamin B12 (400 microg), and pyridoxine (10 mg)--referred to as folate treatment--or placebo was administered to 205 patients (mean [+/-SD] age, 61+/-11 years) for six months after successful coronary angioplasty in a prospective, double-blind, randomized trial. The primary end point was restenosis within six months as assessed by quantitative coronary angiography. The secondary end point was a composite of major adverse cardiac events. RESULTS Base-tine characteristics and initial angiographic results after coronary angioplasty were similar in the two study groups. Folate treatment significantly lowered plasma homocysteine levels from 11.1+/-4.3 to 7.2+/-2.4 micromol per liter (P<0.001). At follow-up, the minimal luminal diameter was significantly larger in the group assigned to folate treatment (1.72+/-0.76 vs. 1.45+/-0.88 mm, P=0.02), and the degree of stenosis was less severe (39.9+/-20.3 vs. 48.2+/-28.3 percent, P=0.01). The rate of restenosis was significantly lower in patients assigned to folate treatment (19.6 vs. 37.6 percent, P=0.01), as was the need for revascularization of the target lesion (10.8 vs. 22.3 percent, P=0.047). CONCLUSIONS Treatment with a combination of folic acid, vitamin B12, and pyridoxine significantly reduces homocysteine levels and decreases the rate of restenosis and the need for revascularization of the target lesion after coronary angioplasty. This inexpensive treatment, which has minimal side effects, should be considered as adjunctive therapy for patients undergoing coronary angioplasty.
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Affiliation(s)
- G Schnyder
- Division of Cardiology, Swiss Cardiovascular Center Bern, University Hospital.
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Seiler C, Pohl T, Wustmann K, Hutter D, Nicolet PA, Windecker S, Eberli FR, Meier B. Promotion of collateral growth by granulocyte-macrophage colony-stimulating factor in patients with coronary artery disease: a randomized, double-blind, placebo-controlled study. Circulation 2001; 104:2012-7. [PMID: 11673338 DOI: 10.1161/hc4201.097835] [Citation(s) in RCA: 225] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Experimentally, activated macrophages have been documented to induce vascular proliferation. METHODS AND RESULTS In 21 patients (age 74+/-9 years) with extensive coronary artery disease not eligible for coronary artery bypass surgery, the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF, Molgramostim) on quantitatively assessed collateral flow was tested in a randomized, double-blind, placebo-controlled fashion. The study protocol consisted of an invasive collateral flow index (CFI) measurement immediately before intracoronary injection of 40 microg of GM-CSF (n=10) or placebo (n=11) and after a 2-week period with subcutaneous GM-CSF (10 microg/kg) or placebo, respectively. CFI was determined by simultaneous measurement of mean aortic pressure (P(ao), mm Hg), distal coronary occlusive pressure (P(occl), mm Hg; using intracoronary sensor guidewires), and central venous pressure (CVP, mm Hg): CFI=(P(occl)-CVP)/(P(ao)-CVP). CFI, expressing collateral flow during coronary occlusion relative to normal antegrade flow during vessel patency, changed from 0.21+/-0.14 to 0.31+/-0.23 in the GM-CSF group (P<0.05) and from 0.30+/-0.16 to 0.23+/-0.11 in the placebo group (P=NS). The treatment-induced difference in CFI was +0.11+/-0.12 in the GM-CSF group and -0.07+/-0.12 in the placebo group (P=0.01). ECG signs of myocardial ischemia during coronary balloon occlusion occurred in 9 of 10 patients before and 5 of 10 patients after GM-CSF treatment (P=0.04), whereas they were observed in 5 of 11 patients before and 8 of 11 patients after placebo (P=NS). CONCLUSIONS This first clinical study investigating the potential of GM-CSF to improve collateral flow in patients with coronary artery disease documents its efficacy in a short-term administration protocol.
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Affiliation(s)
- C Seiler
- Swiss Cardiovascular Center Bern, Cardiology, University Hospital, Bern, Switzerland.
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20
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Varma N, Eberli FR, Apstein CS. Left ventricular diastolic dysfunction during demand ischemia: rigor underlies increased stiffness without calcium-mediated tension. Amelioration by glycolytic substrate. J Am Coll Cardiol 2001; 37:2144-53. [PMID: 11419901 DOI: 10.1016/s0735-1097(01)01282-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVES The goal of this study was to determine the subcellular mechanism(s) underlying increased left ventricular (LV) diastolic chamber stiffness (DCS) during angina (demand ischemia). BACKGROUND Increased DCS may result from increased diastolic myocyte calcium concentration and/or rigor. Therefore, we assessed the effects of direct alterations of both calcium-activated tension and high-energy phosphates on increased DCS. METHODS Demand ischemia was reproduced in isolated, isovolumic, red-cell perfused rabbit hearts by imposing low-flow ischemia and pacing tachycardia. This resulted in increased DCS. Interventions were performed after LV end-diastolic pressure had increased approximately 7 mm Hg. Initially, to determine the effects of altered calcium concentration or myofilament calcium responsiveness, hearts received either: 1) 5 or 14 mmol/L calcium chloride; 2) 8 mmol/L egtazic acid; 3) 5 mmol/L butane-dione-monoxime (BDM); or 4) 50 mmol/L ammonium chloride (NH4Cl). Then, to assess the contribution of decreased high-energy phosphate supply, hearts received 5) glucose (25 mmol/L) and insulin (400 microU/ml). RESULTS 1) Calcium chloride, 5 and 14 mmol/L, increased LV systolic pressure by 42% and 70%, respectively (p < 0.001), indicating increased calcium-activated tension, but did not further increase DCS, implying intact diastolic calcium resequestration. 2) Egtazic acid reduced LV systolic pressure by 30% (p < 0.001), indicating reduced intracellular calcium, but failed to reduce increased DCS. 3) Butane-dione-monoxime and NH4Cl chloride affected contractile function (i.e., a calcium-driven force) but did not alter increased DCS. 4) Glucose and insulin, which increase high-energy phosphates during ischemia, reduced increased DCS by 50% (p < 0.001). CONCLUSIONS Increased DCS during demand ischemia was insensitive to maneuvers altering intracellular calcium concentration or myofilament calcium-responsiveness, that is, evidence against an etiology of calcium-activated tension. In contrast, increased glycolytic substrate ameliorated increased DCS, supporting a primary mechanism of rigor-bond formation.
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Affiliation(s)
- N Varma
- Boston University School of Medicine, Masachusetts 02118, USA.
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21
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Affiliation(s)
- N Kucher
- Dept of Cardiology, Swiss Cardiovascular Center Bern, University Hospital, Bern, Switzerland
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Abstract
BACKGROUND Patent foramen ovale (PFO) and atrial septal aneurysm (ASA) have been associated with stroke in young adults. Patients with PFO suffering from paradoxical embolism are at increased risk for recurrent events. Percutaneous PFO closure is a new treatment modality aimed at secondary prevention. METHODS AND RESULTS Since April 1994, 132 consecutive patients, aged 51 +/- 12 years with PFO and with at least one paradoxical embolic event, underwent percutaneous PFO closure using six different device types. The embolic index event was an ischemic stroke in 62% of patients, a transient ischemic attack (TIA) in 33% of patients, and a peripheral embolism in 5% of patients. Thirty-six (27%) patients had PFO associated with ASA, whereas 96 (73%) patients had PFO only. The implantation procedure was successful in 130 (98%) patients. During and up to 6 years of follow-up (mean 1.8 +/- 1.6 years, 231 patient years), a total of eight recurrent embolic events were observed, with six TIAs, two peripheral emboli, and no ischemic stroke. The actuarial freedom from recurrence of the combined end point of TIA, ischemic stroke, and peripheral embolism was 95.3% (95% confidence interval [CI], 91.0%-96.4%) at 1 year and 90.5% (95% CI, 83.6%-97.2%) at 6 years. CONCLUSIONS Percutaneous PFO closure can be performed with a high success rate. The procedure appears a promising therapeutic modality for secondary prevention of recurrent embolism in patients with PFO. Randomized trials must define its therapeutic value.
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Affiliation(s)
- A Wahl
- Swiss Cardiovascular Center Bern, University Hospital, CH-3010 Bern, Switzerland
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Podesser BK, Siwik DA, Eberli FR, Sam F, Ngoy S, Lambert J, Ngo K, Apstein CS, Colucci WS. ET(A)-receptor blockade prevents matrix metalloproteinase activation late postmyocardial infarction in the rat. Am J Physiol Heart Circ Physiol 2001; 280:H984-91. [PMID: 11179039 DOI: 10.1152/ajpheart.2001.280.3.h984] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Endothelin (ET) A (ET(A)) receptors activate matrix metalloproteinases (MMP). Since endothelin-1 (ET) is increased in myocardium late postmyocardial infarction (MI), we hypothesized that stimulation of ET(A) receptors contributes to activation of myocardial MMPs late post-MI. Three days post-MI, rats were randomized to treatment with the ET(A)-selective receptor antagonist sitaxsentan (n = 12) or a control group (n = 12). Six weeks later, there were rightward shifts of the left ventricular (LV) end-diastolic and end-systolic pressure-volume relationships, as measured ex vivo by the isovolumic Langendorff technique. Both shifts were markedly attenuated by sitaxsentan. In LV myocardium remote from the infarct, the activities of MMP-1, MMP-2, and MMP-9 were increased in the post-MI group, and the increases were prevented by sitaxsentan treatment. Expression of tissue inhibitor of MMP-1 was decreased post-MI, and the decrease was prevented by sitaxsentan treatment. Chronic post-MI remodeling is associated with activation of MMPs in myocardium remote from the infarct. Inhibition of ET(A) receptors prevents MMP activation and LV dilation, suggesting that ET, acting via the ET(A) receptor, contributes to chronic post-MI remodeling by its effects on MMP activity.
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Affiliation(s)
- B K Podesser
- Cardiovascular Section, Boston University Medical Center, and Myocardial Biology Unit and Cardiac Muscle Research Laboratory, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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24
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Billinger M, Fleisch M, Eberli FR, Meier B, Seiler C. Collateral and collateral-adjacent hyperemic vascular resistance changes and the ipsilateral coronary flow reserve. Documentation of a mechanism causing coronary steal in patients with coronary artery disease. Cardiovasc Res 2001; 49:600-8. [PMID: 11166273 DOI: 10.1016/s0008-6363(00)00175-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
OBJECTIVES The goal of this clinical study was to assess the influence of hyperemic ipsilateral, collateral and contralateral vascular resistance changes on the coronary flow velocity reserve (CFVR) of the collateral-receiving (i.e. ipsilateral) artery, and to test the validity of a model describing the development of collateral steal. METHODS In 20 patients with one- to two-vessel coronary artery disease (CAD) undergoing angioplasty of one stenotic lesion, adenosine induced intracoronary (i.c.) CFVR during vessel patency was measured using a Doppler guidewire. During stenosis occlusion, simultaneous i.c. distal ipsilateral flow velocity and pressure (P(occl), using a pressure guidewire) as well as contralateral flow velocity measurements via a third i.c. wire were performed before and during intravenous adenosine. From those measurements and simultaneous mean aortic pressure (P(ao)), a collateral flow index (CFI), and the ipsilateral, collateral, and contralateral vascular resistance index (R(ipsi), R(coll), R(contra)) were calculated. The study population was subdivided into groups with CFI<0.15 and with CFI> or =0.15. RESULTS The percentage-diameter coronary artery stenosis (%-S) to be dilated was similar in the two groups: 78+/-10% versus 82+/-12% (NS). CFVR was not associated with %-S. In the group with CFI> or =0.15 but not with CFI<0.15, CFVR was directly and inversely associated with R(coll) and R(contra), respectively. CONCLUSIONS A hemodynamic interaction between adjacent vascular territories can be documented in patients with CAD and well developed collaterals among those regions. The CFVR of a collateralized region may, thus, be more dependent on hyperemic vascular resistance changes of the collateral and collateral-supplying area than on the ipsilateral stenosis severity, and may even fall below 1.
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Affiliation(s)
- M Billinger
- University Hospital, Swiss Cardiovascular Center Bern, Cardiology, Bern, Switzerland
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25
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Abstract
In situations such as severe low-flow ischemia, where myocardial work output is low and dependence on anaerobic glycolysis is high, increasing the myocardial supply of glucose and insulin is cardioprotective. Our goal was to determine whether this strategy of "metabolic support" would also be cardioprotective in the moderately hypoperfused heart receiving inotropic stimulation, i.e. when myocardial work was near normal, and reliance on anaerobic glycolysis was minimal. Isovolumic left ventricular performance and cardiac energetics (31P-NMR spectroscopy) were measured in 20 isolated rat hearts perfused with red blood cell containing perfusate (hematocrit 40%) with either normal (5 m M, 15 microU/ml) or increased (19.5 m M, 250 microU/ml) glucose and insulin in addition to normal levels of lactate and free fatty acids. Lowering global coronary flow to 30% of normal decreased left ventricle developed pressure by 50%. Administering dobutamine for 40 min restored developed pressure to 95+/-13% of baseline but caused diastolic pressure to increase by 23+/-6 mmHg and [ATP] to decrease by 44+/-6%. Glucose and insulin prevented the increase in end-diastolic pressure, and [ATP] fell by only 14+/-3%. Despite these improvements in cardiac energetics and diastolic function, left ventricle developed pressure was not improved by increased glucose and insulin during, or after the hypoperfusion. We conclude that inotropic support of the hypoperfused heart can cause new diastolic dysfunction, but that this diastolic dysfunction can be eliminated by preserving myocardial high-energy phosphates with increased glucose and insulin.
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Affiliation(s)
- K W Saupe
- Cardiac Muscle Research Laboratory, Boston University School of Medicine, 650 Albany St, X720, Boston, MA 02118, USA.
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26
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Abstract
Mechanical compression of coronary artery stents may be associated with a fatal outcome as the result of refractory myocardial ischemia. We present the history of an 83-yr-old patient, who died owing to hemorrhagic shock 3 days after stent implantation, despite immediate cardiopulmonary resuscitation (CPR). Postmortem examination showed stent compression, probably due to mechanical deformation during CPR. This complication has been reported in two other cases in the literature, suggesting that CPR may be hazardous to patients with coronary artery stents.
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Affiliation(s)
- S Windecker
- Swiss Cardiovascular Center, University Hospital, Bern, Switzerland
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27
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Abstract
BACKGROUND Ischemia is characterized by an increase in intracellular calcium and occurrence of diastolic dysfunction. We investigated whether the myocyte calcium level is an important direct determinant of ischemic diastolic dysfunction. METHODS AND RESULTS We exposed isolated, perfused isovolumic (balloon in left ventricle) rat and rabbit hearts to low-flow ischemia and increased extracellular calcium (from 1.5 to 16 mmol/L) for brief periods. Intracellular calcium was measured by aequorin. Low-flow ischemia resulted in a 270% increase (P:<0.05) in diastolic intracellular calcium, a 50% (P:<0.05) calcium transient amplitude decrease, and a 52% (P:<0.05) slowing of calcium transient decline. Diastolic pressure increased by 6+/-2 mm Hg (P:<0.05), and rate of systolic pressure decay decreased by 65% (P:<0.05). Experimentally increasing extracellular calcium doubled both intracellular diastolic calcium and calcium transient amplitude, concomitant with a developed pressure increase; however, there was no increase in ischemic diastolic pressure, slowing of the calcium transient decay, or further slowing of systolic pressure decay. Similarly, after 45 minutes of low-flow ischemia, after diastolic pressure had increased from 8.5+/-0.6 to 19.7+/-3.5 mm Hg (P:<0.001), intracoronary high-molar calcium chloride infusion increased systolic pressure from 36+/-4 to 63+/-11 mm Hg (P:<0.001), indicating an increase in intracellular calcium, but it decreased diastolic pressure from 19. 7+/-3.5 to 17.5+/-3.7 mm Hg (P:<0.01). Conversely, EGTA infusion decreased systolic pressure, indicating a decrease in intracellular calcium, but did not decrease diastolic pressure. CONCLUSIONS When calcium availability was experimentally altered during ischemia, there was no alteration in left ventricular diastolic pressure, suggesting that ischemic diastolic dysfunction is not directly mediated by a calcium activated tension.
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Affiliation(s)
- F R Eberli
- Cardiac Muscle Research Laboratory, Boston University School of Medicine, Boston, MA, USA
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28
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Nagata K, Communal C, Lim CC, Jain M, Suter TM, Eberli FR, Satoh N, Colucci WS, Apstein CS, Liao R. Altered beta-adrenergic signal transduction in nonfailing hypertrophied myocytes from Dahl salt-sensitive rats. Am J Physiol Heart Circ Physiol 2000; 279:H2502-8. [PMID: 11045988 DOI: 10.1152/ajpheart.2000.279.5.h2502] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Desensitization of the beta-adrenergic receptor (beta-AR) response is well documented in hypertrophied hearts. We investigated whether beta-AR desensitization is also present at the cellular level in hypertrophied myocardium, as well as the physiological role of inhibitory G (G(i)) proteins and the L-type Ca(2+) channel in mediating beta-AR desensitization. Left ventricular (LV) myocytes were isolated from hypertrophied hearts of hypertensive Dahl salt-sensitive (DS) rats and nonhypertrophied hearts of normotensive salt-resistant (DR) rats. Cells were paced at a rate of 300 beats/min at 37 degrees C, and myocyte contractility and intracellular Ca(2+) concentration ([Ca(2+)](i)) were simultaneously measured. In response to increasing concentrations of isoproterenol, DR myocytes displayed a dose-dependent augmentation of cell shortening and the [Ca(2+)](i) transient amplitude, whereas hypertrophied DS myocytes had a blunted response of both cell shortening and the [Ca(2+)](i) transient amplitude. Interestingly, inhibition of G(i) proteins did not restore beta-AR desensitization in DS myocytes. The responses to increases in extracellular Ca(2+) and an L-type Ca(2+) channel agonist were also similar in both DS and DR myocytes. Isoproterenol-stimulated adenylyl cyclase activity, however, was blunted in hypertrophied myocytes. We concluded that compensated ventricular hypertrophy results in a blunted contractile response to beta-AR stimulation, which is present at the cellular level and independent of alterations in inhibitory G proteins and the L-type Ca(2+) channel.
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MESH Headings
- Adenylate Cyclase Toxin
- Adenylyl Cyclases/drug effects
- Adenylyl Cyclases/metabolism
- Adrenergic beta-Agonists/pharmacology
- Animals
- Calcium/metabolism
- Calcium Channel Agonists/pharmacology
- Calcium Channels, L-Type/drug effects
- Calcium Channels, L-Type/metabolism
- Disease Models, Animal
- Dose-Response Relationship, Drug
- GTP-Binding Protein alpha Subunits, Gi-Go/antagonists & inhibitors
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- Guanylyl Imidodiphosphate/pharmacology
- Heart Function Tests
- Hypertrophy, Left Ventricular/metabolism
- In Vitro Techniques
- Isoproterenol/pharmacology
- Male
- Manganese/pharmacology
- Myocardial Contraction/drug effects
- Myocardium/metabolism
- Myocardium/pathology
- Rats
- Rats, Inbred Dahl
- Receptors, Adrenergic, beta/metabolism
- Signal Transduction/drug effects
- Virulence Factors, Bordetella/pharmacology
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Affiliation(s)
- K Nagata
- First Department of Internal Medicine, Nagoya University School of Medicine, Nagoya 466-8550, Japan
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29
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Roffi M, Mahler F, Eberli FR. Images in cardiology. Thromboembolic leg ischaemia as first manifestation of an unrecognised myocardial infarction. Heart 2000; 84:207. [PMID: 10908263 PMCID: PMC1760895 DOI: 10.1136/heart.84.2.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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30
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Sam F, Sawyer DB, Chang DL, Eberli FR, Ngoy S, Jain M, Amin J, Apstein CS, Colucci WS. Progressive left ventricular remodeling and apoptosis late after myocardial infarction in mouse heart. Am J Physiol Heart Circ Physiol 2000; 279:H422-8. [PMID: 10899082 DOI: 10.1152/ajpheart.2000.279.1.h422] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We tested the hypothesis that left ventricular (LV) remodeling late after myocardial infarction (MI) is associated with myocyte apoptosis in myocardium remote from the infarcted area and is related temporally to LV dilation and contractile dysfunction. One, four, and six months after MI caused by coronary artery ligation, LV volume and contractile function were determined using an isovolumic balloon-in-LV Langendorff technique. Apoptosis and nuclear morphology were determined by terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) and Hoechst 33258 staining. Progressive LV dilation 1-6 mo post-MI was associated with reduced peak LV developed pressure (LVDP). In myocardium remote from the infarct, there was increased wall thickness and expression of atrial natriuretic peptide mRNA consistent with reactive hypertrophy. There was a progressive increase in the number of TUNEL-positive myocytes from 1 to 6 mo post-MI (2.9-fold increase at 6 mo; P < 0. 001 vs. sham). Thus LV remodeling late post-MI is associated with increased apoptosis in myocardium remote from the area of ischemic injury. The frequency of apoptosis is related to the severity of LV dysfunction.
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Affiliation(s)
- F Sam
- Cardiovascular Section, Boston University Medical Center, Myocardial Biology Unit and Cardiac Muscle Research Laboratory, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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31
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Varma N, Eberli FR, Apstein CS. Increased diastolic chamber stiffness during demand ischemia: response to quick length change differentiates rigor-activated from calcium-activated tension. Circulation 2000; 101:2185-92. [PMID: 10801760 DOI: 10.1161/01.cir.101.18.2185] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Increased diastolic chamber stiffness (increased DCS) during angina (demand ischemia) has been postulated to be generated by increased diastolic myocyte calcium concentration. METHODS AND RESULTS We reproduced demand ischemia in isolated isovolumically contracting red-cell-perfused rabbit hearts by imposing pacing tachycardia during global low coronary blood flow (32% of baseline). This increased lactate production without increasing oxygen consumption and resulted in increased DCS (isovolumic left ventricular end-diastolic pressure [LVEDP] increased 10 mm Hg, P<0. 001, n=38). To determine the mechanism of increased DCS, we assessed responses to a quick-stretch-release maneuver (QSR), in which the intraventricular balloon was rapidly inflated and deflated to achieve a 3% circumferential muscle fiber length change. QSR was first validated as an effective method of discriminating between calcium-driven and rigor-mediated increased DCS. QSR imposed during demand ischemia when DCS had increased (LVEDP pretachycardia versus posttachycardia, 15+/-1 versus 27+/-2 mm Hg, P<0.001, n=6) reduced DCS to pretachycardia values (LVEDP post-QSR, 15+/-1 mm Hg, P<0.001), ie, elicited a response characteristic of rigor, without any component of calcium-generated tension. CONCLUSIONS A rigor force, possibly resulting from high-energy phosphate depletion and/or an increase in ADP, appears to be the primary mechanism underlying increased DCS in this model of global LV demand ischemia.
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Affiliation(s)
- N Varma
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA 02118, USA
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32
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Abstract
BACKGROUND Our goals were to (1) simulate the degree of low-flow ischemia and mixed anaerobic and aerobic metabolism of an acutely infarcting region; (2) define changes in anaerobic glycolysis, oxidative phosphorylation, and the creatine kinase (CK) reaction velocity; and (3) determine whether and how increased glycolytic substrate alters the energetic profile, function, and recovery of the ischemic myocardium in the isolated blood-perfused rat heart. METHODS AND RESULTS Hearts had 60 minutes of low-flow ischemia (10% of baseline coronary flow) and 30 minutes of reperfusion with either control or high glucose and insulin (G+I) as substrate. In controls, during ischemia, rate-pressure product and oxygen consumption decreased by 84%. CK velocity decreased by 64%; ATP and phosphocreatine (PCr) concentrations decreased by 51% and 63%, respectively; inorganic phosphate (P(i)) concentration increased by 300%; and free [ADP] did not increase. During ischemia, relative to controls, the G+I group had similar CK velocity, oxygen consumption, and tissue acidosis but increased glycolysis, higher [ATP] and [PCr], and lower [P(i)] and therefore had a greater free energy yield from ATP hydrolysis. Ischemic systolic and diastolic function and postischemic recovery were better. CONCLUSIONS During low-flow ischemia simulating an acute myocardial infarction region, oxidative phosphorylation accounted for 90% of ATP synthesis. The CK velocity fell by 66%, and CK did not completely use available PCr to slow ATP depletion. G+I, by increasing glycolysis, slowed ATP depletion, maintained lower [P(i)], and maintained a higher free energy from ATP hydrolysis. This improved energetic profile resulted in better systolic and diastolic function during ischemia and reperfusion. These results support the clinical use of G+I in acute MI.
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Affiliation(s)
- A C Cave
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
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33
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Abstract
Comparisons of myocardium remodeled by the 2 most common causes of left ventricular hypertrophy (LVH), hypertension and aortic constriction, are limited. We hypothesized that important differences may exist in the myocardium of hearts with these 2 origins of "pressure overload" LVH. Accordingly, we studied isolated hearts from 3 groups of Dahl salt-sensitive rats, controls, and hearts with matched amounts of LVH secondary to either hypertension or aortic constriction. Isovolumic LV function and myocardial energetics ((31)P nuclear magnetic resonance spectroscopy) were measured as coronary flow was lowered to 16% of baseline for 48 minutes. During this low-flow ischemia, isovolumic end-diastolic pressure, a measure of LV stiffness, increased to 52+/-4 mm Hg in controls and 51+/-6 mm Hg in aortic banded hearts but to only 35+/-5 mm Hg in hearts with hypertensive LVH. In all hearts, the P(i) resonance in the (31)P nuclear magnetic resonance spectrum, whose position indicates myocardial pH, split into 2 peaks during low-flow ischemia, which indicates distinct regions of pH 6.9 (moderate acidosis) and pH 6.2 (severe acidosis). Concentrations of ATP, PCr, P(i), and H(+) of the moderately acidotic region were not different among groups. However, the size of the severely acidotic region was smallest in the hypertensive LVH hearts, and in all 3 groups, the size of this region correlated (r(2)=0.65 to 0.80) with the degree of LV stiffening. We conclude that in Dahl rats, LVH secondary to hypertension protects against ischemia-induced diastolic dysfunction by minimizing the size of the region of severe acidosis.
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Affiliation(s)
- K W Saupe
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, MA 02118, USA.
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34
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Jain M, Liao R, Ngoy S, Whittaker P, Apstein CS, Eberli FR. Angiotensin II receptor blockade attenuates the deleterious effects of exercise training on post-MI ventricular remodelling in rats. Cardiovasc Res 2000; 46:66-72. [PMID: 10727654 DOI: 10.1016/s0008-6363(99)00429-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES The effects of exercise training on LV remodelling following large anterior myocardial infarction (MI) remains controversial. Blockade of the renin-angiotensin system has been shown to prevent ventricular dilation and deleterious remodeling. We therefore tested, in a rat model of chronic MI, whether any potentially deleterious effects of exercise on post-MI remodelling could be ameliorated by angiotensin II receptor blockade. METHODS Male Wistar rats underwent coronary ligation or sham operation. Treatment with losartan (10 mg/kg/day) began 1 week post-MI and moderate treadmill exercise (25 m/min, 60 min/day, 5 days/week) was initiated 2 weeks post-MI. Systolic and diastolic pressure-volume relationships were measured in isolated, red-cell perfused, isovolumically beating hearts 8 weeks post-MI. Morphometric measurements were performed in trichrome stained cross sections of the heart. Five groups of animals were compared: sham (n=13), control MI (MI; n=11), MI plus losartan (MI-Los; n=13), MI plus exercise (MI-Ex; n=10) and MI plus exercise and losartan (MI-Ex-Los; n=12). RESULTS Infarct size (% of left ventricle, LV) was similar among the infarcted groups [MI=43+/-4%, MI-Los=49+/-2%, MI-Ex=45+/-1%, MI-Ex-Los=48+/-2% (NS)]. Exercise, losartan and exercise+losartan treatments all attenuated LV dilation post-MI to a similar degree. Exercise training increased LV developed pressure in both untreated and losartan treated hearts (P<0.05 vs. other MI groups). In addition, exercise resulted in additional scar thinning in untreated hearts, while no additional scar thinning was seen in post-infarct hearts receiving both losartan and exercise. CONCLUSIONS Following large anterior MI, losartan attenuated LV dilation and scar thinning. In untreated animals, exercise decreased dilation, but also contributed to scar thinning. Therefore, exercise concurrent with blockade of the renin-angiotensin system may provide optimal therapeutic benefit following large anterior MI.
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Affiliation(s)
- M Jain
- The Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA, USA
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35
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Abstract
Primary diastolic failure is typically seen in patients with hypertensive or valvular heart disease as well as in hypertrophic or restrictive cardiomyopathy but can also occur in a variety of clinical disorders, especially tachycardia and ischemia. Diastolic dysfunction has a particularly high prevalence in elderly patients and is generally associated, with low mortality but high morbidity. The pathophysiology of diastolic dysfunction includes delayed relaxation, impaired LV filling and/or increased stiffness. These conditions result typically in an upward displacement of the diastolic pressure-volume relationship with increased end-diastolic, left atrial and pulmo-capillary wedge pressure leading to symptoms of pulmonary congestion. Diagnosis of diastolic heart failure requires three conditions: (1) presence of signs or symptoms of heart failure; (2) presence of normal or slightly reduced LV ejection fraction (EF > 50%) and (3) presence of increased diastolic filling pressure. Assessment of diastolic function can be performed with several non-invasive (2D- and Doppler-echocardiography, color Doppler M-mode, Doppler tissue imaging, MR-myocardial tagging, radionuclide ventriculography) and invasive techniques (micromanometry, angiography, conductance method). Doppler-echocardiography is the most useful tool to routinely measure diastolic function. Different techniques can be used alone or in combination to assess LV diastolic function, but most of them are dependent on heart rate, pre- and afterload. The transmitral flow pattern remains the starting point, since it is easy to acquire and rapidly categorizes patients into normal (E > A), delayed relaxation (E < A), and restrictive (E >> A) filling patterns. Invasive assessment of diastolic function allows determination of the time constant of relaxation from the exponential pressure decay during isovolumic relaxation, and the evaluation of the passive elastic properties from the slope of the diastolic pressure-volume (= constant of chamber stiffness) and stress-strain relationship (= constant of myocardial stiffness). The prognosis of diastolic heart failure is usually better than for systolic dysfunction. Diastolic heart failure is associated with a lower annual mortality rate of approximately 8% as compared to annual mortality of 19% in heart failure with systolic dysfunction, however, morbidity rate can be substantial. Thus, diastolic heart failure is an important clinical disorder mainly seen in the elderly patients with hypertensive heart disease. Early recognition and appropriate therapy of diastolic dysfunction is advisable to prevent further progression to diastolic heart failure and death. There is no specific therapy to improve LV diastolic function directly. Medical therapy of diastolic dysfunction is often empirical and lacks clear-cut pathophysiologic concepts. Nevertheless, there is growing evidence that calcium channel blockers, beta-blockers, ACE-inhibitors and AT2-blockers as well as nitric oxide donors can be beneficial. Treatment of the underlying disease is currently the most important therapeutic approach.
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Affiliation(s)
- L Mandinov
- Swiss Cardiovascular Center, University Hospital, Bern, Switzerland
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36
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Windecker S, Wahl A, Chatterjee T, Garachemani A, Eberli FR, Seiler C, Meier B. Percutaneous closure of patent foramen ovale in patients with paradoxical embolism: long-term risk of recurrent thromboembolic events. Circulation 2000; 101:893-8. [PMID: 10694529 DOI: 10.1161/01.cir.101.8.893] [Citation(s) in RCA: 308] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Patients with a patent foramen ovale (PFO) and paradoxical embolism are at risk for recurrent thromboembolic events. This study investigated the long-term risk of recurrent thromboembolic events in patients with PFO and paradoxical embolism after percutaneous PFO closure. METHODS AND RESULTS Since 1994, a total of 80 patients with PFO and at least 1 paradoxical embolic event (transient ischemic attack [TIA], cerebrovascular accident [CVA], peripheral embolism) have undergone percutaneous PFO closure with 5 different devices. There were 30 women and 50 men, with a mean age of 52+/-12 years. Sixty patients had only a PFO, whereas 20 patients had both a PFO and an atrial septal aneurysm. The implantation procedure was successful in 78 patients (98%). During 5 years of follow-up (mean, 1.6+/-1.4 years; range, 0.1 to 5.0 years), the actuarial annual risk to suffer a recurrent thromboembolic event was 2.5% for TIA, 0% for CVA, 0.9% for peripheral emboli, and 3.4% for the combined end point of TIA, CVA, or peripheral embolism. A postprocedural shunt was a predictor of recurrent paradoxical embolism (RR, 4.2; 95% CI, 1.1 to 17.8; P=0.03). The risk for recurrent thromboembolic events in patients with both atrial septal aneurysm and PFO was not significantly increased compared with patients with only PFO (RR, 1.0; 95% CI, 0.2 to 4.7; P=0.95). CONCLUSIONS Percutaneous PFO closure appears to be a promising technique in the prevention of recurrent systemic thromboembolism in patients with a PFO after a first event. Prospective studies comparing percutaneous PFO closure with antithrombotic medications or surgery must define its therapeutic value.
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Affiliation(s)
- S Windecker
- Swiss Cardiovascular Center Bern, University Hospital, Bern, Switzerland
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37
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Fleisch M, Billinger M, Eberli FR, Garachemani AR, Meier B, Seiler C. Physiologically assessed coronary collateral flow and intracoronary growth factor concentrations in patients with 1- to 3-vessel coronary artery disease. Circulation 1999; 100:1945-50. [PMID: 10556219 DOI: 10.1161/01.cir.100.19.1945] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The purpose of this study was to test the hypothesis that there is a relation between collateral flow and intracoronary concentrations of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) and that the combined concentrations of both growth factors and the extent of coronary artery disease (CAD) play a role as covariables in such an association. METHODS AND RESULTS In 76 patients undergoing balloon angioplasty, a collateral flow index (CFI, no units) was determined with sensor-tipped guidewires. Simultaneously, serum concentrations of bFGF and VEGF, obtained at the aortic root from the ostium of the collateralized coronary artery (n = 76) and from the distal position of the occluded coronary artery (n = 34), were determined. There was a direct correlation between CFI and distal VEGF (r = 0.33, P = 0.05) but not bFGF concentrations. Focusing on the proximal sampling site, there was a direct correlation between CFI and both bFGF (r = 0.29, P = 0.01) and VEGF concentrations (r = 0.44, P < 0.0001). The sum of the concentrations of both growth factors was directly associated with CFI irrespective of the proximal (r = 0.51, P < 0.0001) or distal sampling site (r = 0.34, P = 0.048). There was a trend toward higher proximal VEGF concentrations in patients with higher numbers of coronary stenotic lesions (r = 0.25, P = 0.03). CONCLUSIONS In patients with CAD, there is an association between a directly measured index of collateral flow and intracoronary concentrations of bFGF and VEGF. This direct relation is dependent on the site of blood sampling within the coronary artery tree. The association is closest when the combined bFGF and VEGF concentrations are taken into account. In the case of VEGF, it is influenced by the degree of coronary atherosclerosis.
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Affiliation(s)
- M Fleisch
- Cardiology, University Hospital, Bern, Switzerland
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38
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Abstract
Decreasing coronary perfusion causes an immediate decrease in contractile function via unknown mechanisms. It has long been suspected that this contractile dysfunction is caused by ischemia-induced changes in cardiac energetics. Our goal was to determine whether changes in cardiac energetics necessarily precede the contractile dysfunction as one would expect if a causal relationship exists. In 14 isolated rat hearts, we gradually decreased coronary perfusion using a coronary perfusate with a normal hematocrit and normal concentrations of the major metabolic substrates. Using 31P NMR spectroscopy to measure ATP, phosphocreatine (PCr), Pi, and ADP concentrations ([ATP], [PCr], [Pi], [ADP]), pH, and amount of free energy released from ATP hydrolysis (|DeltaGATP|), we found that none of these variables changed significantly until several minutes after systolic pressure had significantly decreased. Even when developed pressure had decreased by over one-third, only very slight changes in [Pi], pH, and |DeltaGATP| had occurred, with no significant changes in [ATP], [PCr], or [ADP]. Additionally, the rate of high-energy phosphate transfer between ATP and PCr did not decrease enough during hypoperfusion to explain the contractile dysfunction. We conclude that nonenergetic factors are the dominant cause of the initial decrease in systolic function when myocardial perfusion is decreased.
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Affiliation(s)
- K W Saupe
- Cardiac Muscle Research Laboratory, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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39
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Billinger M, Fleisch M, Eberli FR, Garachemani A, Meier B, Seiler C. Is the development of myocardial tolerance to repeated ischemia in humans due to preconditioning or to collateral recruitment? J Am Coll Cardiol 1999; 33:1027-35. [PMID: 10091831 DOI: 10.1016/s0735-1097(98)00674-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES The purpose of this study in patients with quantitatively determined, poorly developed coronary collaterals was to assess the contribution of ischemic as well as adenosine-induced preconditioning and of collateral recruitment to the development of tolerance against repetitive myocardial ischemia. BACKGROUND The development of myocardial tolerance to repeated ischemia is nowadays interpreted to be due to biochemical adaptation (i.e., ischemic preconditioning). METHODS In 30 patients undergoing percutaneous transluminal coronary angioplasty, myocardial adaptation to ischemia was measured using intracoronary (i.c.) electrocardiographic (ECG) ST segment elevation changes obtained from a 0.014-in. (0.036 cm) pressure guidewire positioned distal to the stenosis during three subsequent 2-min balloon occlusions. Simultaneously, an i.c. pressure-derived collateral flow index (CFI, no unit) was determined as the ratio between distal occlusive minus central venous pressure divided by the mean aortic minus central venous pressure. The study patients were divided into two groups according to the pretreatment with i.c. adenosine (2.4 mg/min for 10 min starting 20 min before the first occlusion, n = 15) or with normal saline (control group, n = 15). RESULTS Collateral flow index at the first occlusion was not different between the groups (0.15 +/- 0.10 in the adenosine group and 0.13 +/- 0.11 in the control group, p = NS), and it increased significantly and similarly to 0.20 +/- 0.14 and to 0.19 +/- 0.10, respectively (p < 0.01) during the third occlusion. The i.c. ECG ST elevation (normalized for the QRS amplitude) was not different between the two groups at the first occlusion (0.25 +/- 0.13 in the adenosine group, 0.25 +/- 0.19 in the control group). It decreased significantly during subsequent coronary occlusions to 0.20 +/- 0.15 and to 0.17 +/- 0.13, respectively. There was a correlation between the change in CFI (first to third occlusion; deltaCFI) and the respective ST elevation shift (deltaST): deltaST = -0.02 to 0.78 x deltaCFI; r = 0.54, p = 0.02. CONCLUSIONS Even in patients with few coronary collaterals, the myocardial adaptation to repetitive ischemia is closely related to collateral recruitment. Pharmacologic preconditioning using a treatment with i.c. adenosine before angioplasty does not occur. The variable responses of ECG signs of ischemic adaptation to collateral channel opening suggest that ischemic preconditioning is a relevant factor in the development of ischemic tolerance.
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Affiliation(s)
- M Billinger
- Division of Cardiology, University Hospital, Bern, Switzerland
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Apstein CS, Eberli FR. Diastolic function and dysfunction with exercise, hypertrophy, ischemia, and heart failure. Cardiologia 1998; 43:1269-79. [PMID: 9988936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Affiliation(s)
- C S Apstein
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Center for Advanced Biomedical Research, Boston University School of Medicine, MA 02118, USA
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41
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Kondo RP, Apstein CS, Eberli FR, Tillotson DL, Suter TM. Increased calcium loading and inotropy without greater cell death in hypoxic rat cardiomyocytes. Am J Physiol 1998; 275:H2272-82. [PMID: 9843829 DOI: 10.1152/ajpheart.1998.275.6.h2272] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To test whether contractile function in "hypoxic" myocytes treated with high glucose (19.5 mM) can be improved by increasing intracellular Ca2+ without accelerating cell contracture or death, we challenged metabolically inhibited, paced myocytes with high extracellular Ca2+ concentration ([Ca2+]o) and measured simultaneously cell shortening and intracellular Ca2+ concentration ([Ca2+]i). NaCN exposure at a physiological [Ca2+]o level (1.2 mM) caused a decline of contractile function to 58 +/- 8% of the pre-NaCN value (P < 0.001) but increased systolic and diastolic [Ca2+]i by 104 +/- 17 and 37 +/- 9% above baseline (P < 0.01), respectively. Consequent doubling of [Ca2+]o to 2.4 mM, in the presence of NaCN, immediately restored contractile function, and twitch amplitude after 18 min was 123 +/- 14% (P < 0.001) of baseline pre-NaCN values, whereas systolic [Ca2+]i increased further to 225 +/- 63% (P < 0.05) and diastolic [Ca2+]i to 73 +/- 16% above baseline (P < 0.01). This marked increase in [Ca2+]i had no deleterious effect on myocyte diastolic function or survival. These results suggest that if adequate metabolic substrate is provided, contractile function in metabolically inhibited, hypoxic myocytes can be restored by increasing [Ca2+]i without causing short-term cell injury.
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Affiliation(s)
- R P Kondo
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston, Massachusetts 02118, USA
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42
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Eberli FR, Meier B. Restenosis after angioplasty: an Achilles' heel well covered-up. Eur Heart J 1998; 19:976-7. [PMID: 9717027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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Eberli FR, Sam F, Ngoy S, Apstein CS, Colucci WS. Left-ventricular structural and functional remodeling in the mouse after myocardial infarction: assessment with the isovolumetrically-contracting Langendorff heart. J Mol Cell Cardiol 1998; 30:1443-7. [PMID: 9710811 DOI: 10.1006/jmcc.1998.0702] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The goal of this study was to determine whether the isovolumically-contracting Langendorff heart could be used to assess changes in left-ventricular volume and contractile reserve in the mouse heart after myocardial infarction. Myocardial infarction (40 +/- 3% of the left ventricle by weight) was induced in CD-1 mice by ligation of the left-anterior descending coronary artery. Two weeks after infarction there was compensatory hypertrophy of the non-infarcted ventricle as indicated by increases in heart-to-body weight ratio (5.5 +/- 0.2 v 4.9 +/- 0.2 mg/g; P < 0.05; n = 12) and the expression of atrial natriuretic peptide mRNA (4.4 +/- 1.4-fold; P < 0.001; n = 4). Left-ventricular pressure-volume relationships were assessed in vitro in isovolumically-contracting hearts perfused with red cell-supplemented buffer (hematrocrit = 40%). Myocardial infarction caused left-ventricular dilation with a rightward-shift of the diastolic pressure-volume relationship. This was associated with reduced left-ventricular contractile function, as evidenced by a decrease in developed pressure over a range of left-ventricular volumes. Thus, it is feasible to use the isovolumically-contracting Langendorff preparation to assess the structural and functional consequences of left-ventricular remodeling in the mouse after a myocardial infarction.
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Affiliation(s)
- F R Eberli
- Cardiac Muscle Research Laboratory, Boston University School of Medicine, MA 92118, USA
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Seiler C, Fleisch M, de Marchi SF, Billinger M, Wahl A, Eberli FR, Garachemani AR, Meier B. Functional assessment of collaterals in the human coronary circulation. Semin Interv Cardiol 1998; 3:13-20. [PMID: 10094180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The coronary collateral circulation is an alternative source of blood supply to a myocardial area jeopardized by the failure of the stenotic or occluded vessel to provide enough blood flow to this region. Until recently, only qualitative or semiqualitative methods have been available for the assessment of the coronary collateral circulation in humans, such as the patient's history of walk-through angina pectoris, the registration of intracoronary ECG signs for myocardial ischaemia or angina pectoris during coronary occlusion, or coronary angiographic classification (score 0-3) of collaterals. Studies of coronary wedge pressure measurements distal of a balloon-occluded coronary artery and the recent advent of ultrathin pressure and Doppler angioplasty guidewires have made it possible to obtain pressure or flow velocity data in remote vascular areas and, thus, to calculate functional variables for coronary collateral flow. Those coronary occlusive pressure- and flow velocity-derived parameters express collateral flow as a fraction of antegrade coronary flow during vessel patency of the collateral-receiving vessel. They are both interchangeable, and they have been validated in comparison to 'traditional' methods and against each other. The possibility of accurately measuring coronary collateral flow indices in humans undergoing coronary balloon angioplasty opens areas of investigation of the pathogenesis, pathophysiology and therapeutic promotion of the collateral circulation previously reserved for exclusively experimental studies. The purpose of this article is to review several clinically available methods for the functional characterization of the coronary collateral circulation.
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Affiliation(s)
- C Seiler
- Cardiology, University Hospital, Berne, Switzerland.
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Nagata K, Liao R, Eberli FR, Satoh N, Chevalier B, Apstein CS, Suter TM. Early changes in excitation-contraction coupling: transition from compensated hypertrophy to failure in Dahl salt-sensitive rat myocytes. Cardiovasc Res 1998; 37:467-77. [PMID: 9614501 DOI: 10.1016/s0008-6363(97)00278-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE The aims were to (1) define the early changes in excitation-contraction coupling during the transition from cardiac hypertrophy to heart failure, and (2) to clarify the causal relationship between mechanical dysfunction and abnormal Ca2+ handling in the Dahl salt-sensitive rat model. METHODS Myocardial contractile function was assessed in whole heart perfusion studies. In separate experiments, isolated left ventricular myocytes from Dahl salt-sensitive (DS) and Dahl salt-resistant (DR) rats were paced at a physiological rate of 5Hz and cell shortening (CS) and [Ca2+]i measured simulataneously by video-edge detection and fura-2 fluorescence. RESULTS DS hearts developed hypertrophy after 4 weeks of a high-salt diet (4WHSD), as indicated by a 26% increase (p < 0.01) in the heart to body weight ratio and a 21% increase (p < 0.01) in cell width. Heart failure developed after 12 weeks of a high-salt diet (12WHSD), as indicated by an 11% increase (p < 0.01) in the lung wet to dry weight ratio. Furthermore, in DS-12WHSD hearts, the diastolic pressure-volume relationship had shifted rightward. DR rats did not develop hypertension and seved as age-matched controls. A 31% (p < 0.05) increase in the %CS in DS-4WHSD myocytes compared to DR-4WHSD myocytes with a trend of a parallel increase in Ca2+ transient amplitude was found. There was no difference in the Ca2+ transient parameters between DR and DS at 12WHSD, but an 18% (p < 0.01) decrease occurred in peak [Ca2+]i in DS myocytes between 4WHSD and 12WHSD. In DS-12WHSD, the time to peak shortening and the time from peak shortening to 50% and 90% relaxation was significantly prolonged by 27%, 44%, and 38%, respectively, as compared to the age-matched DR myocytes. CONCLUSION Our results indicated that: (I) normal Ca2+ homeostasis is preserved at the stage of compensated hypertrophy; (2) the early signs of isolated myocyte dysfunction were a prolongation of the shortening and relaxation time course without an abnormal time course of the Ca2+ transient. Thus, in the hypertensive Dahl salt rat model, abnormal Ca2+ handling appears neither to precede nor initiate the transition to failure.
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Affiliation(s)
- K Nagata
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA 02118, USA
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Julius BK, Spillmann M, Vassalli G, Villari B, Eberli FR, Hess OM. Angina pectoris in patients with aortic stenosis and normal coronary arteries. Mechanisms and pathophysiological concepts. Circulation 1997; 95:892-8. [PMID: 9054747 DOI: 10.1161/01.cir.95.4.892] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND The incidence of angina pectoris (AP) in patients with severe aortic stenosis (AS) and normal coronary arteries has been reported to be 30% to 40%. The exact pathophysiological mechanism, however, is not known. The purpose of this work was to evaluate the various hemodynamic and angiographic determinants of myocardial perfusion in 61 patients with severe AS. METHODS AND RESULTS In a retrospective analysis, 61 patients with severe AS and without significant coronary artery disease were studied. Thirty-three patients with atypical chest pain and angiographically normal arteries served as control subjects. Patients were divided into two groups: 32 with AP and 29 without AP. Quantitative coronary angiography was performed in 59 patients and 22 control subjects. Coronary flow reserve was determined in 29 patients and 7 control subjects by use of coronary sinus thermodilution technique. Patients with AP had a lower left ventricular (LV) muscle mass, an increased LV peak systolic pressure, and increased wall stress than those without AP. Vessels of the left coronary artery were smaller and coronary flow reserve was lower in patients with AP than in those without. Inadequate L V hypertrophy with an increased wall stress was found in patients with AP but not in patients without AP. CONCLUSIONS Myocardial ischemia in patients with severe AS can occur in the absence of coronary artery disease and appears to be due to inadequate LV hypertrophy with high systolic and diastolic wall stresses and a reduced coronary flow reserve. The cause of inadequate LV hypertrophy, however, remains unclear.
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Affiliation(s)
- B K Julius
- Division of Cardiology, University Hospital, Zurich, Switzerland
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Libonati JR, Eberli FR, Sesselberg HW, Apstein CS. Effects of low-flow ischemia on the positive inotropic action of angiotensin II in isolated rabbit and rat hearts. Cardiovasc Res 1997; 33:71-81. [PMID: 9059530 DOI: 10.1016/s0008-6363(96)00185-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
OBJECTIVE Angiotensin II (ANG II) has recently been reported to increase inotropy in adult rabbit myocytes by a mechanism of alkalinization and consequent increased myofilament sensitivity to calcium. Accordingly, we tested the hypothesis that ANG II would have a greater inotropic effect during ischemic conditions than it would during normoxia, since ischemia-induced intracellular acidosis contributes to ischemic contractile depression by decreasing myofilament calcium sensitivity. METHODS We studied the effects of ANG II in isolated, red-blood-cell-perfused, isovolumic rat and rabbit hearts during normoxic perfusion conditions and at graded reductions in coronary perfusion pressure (CPP). At each level of perfusion, ANG II was infused at progressively increasing concentrations ranging from 10(-11) to 10(-5) M. The maximal effective ANG II concentration was 10(-7) M. RESULTS Our studies show that ANG II caused comparable absolute increases in isovolumic LV developed pressure in normoperfused and hypoperfused rabbit hearts. However, since contractile function was markedly depressed in ischemic hearts prior to ANG II administration, the relative inotropic response to ANG II was significantly greater during ischemia than normoxia. Similarly, ANG II had no positive inotropic effect in the rat during normoxia, but increased contractility during ischemia. To assess specifically the potential of ANG II to reverse the negative inotropy of acidosis, normoxic non-ischemic rat hearts were perfused with a hypercarbic acidotic perfusate (pH = 7.1). During the hypercarbic perfusion when contraction was depressed by acidosis, ANG II [10(-7)]M increased LV developed pressure by 19% and +dP/dt by 27% (P < 0.05), in contrast to its lack of intropic effect at a normal pH. The positive inotropic effect observed in rat hearts with ANG II during ischemia was significantly attenuated (P < 0.001) by concomitant infusion with amiloride, 5-(N-ethyl-N-isopropyl) (EIPA), a Na+/H+ exchange inhibitor. CONCLUSIONS We conclude that during normoxia, ANG II has a different inotropic potency in rabbits from that in rats. In both species, the relative inotropic responsiveness of ANG II is potentiated during low-flow ischemia. These results are consistent with a relative intracellular alkalinization that occurs secondary to ANG II's action to stimulate Na+/H+ exchange.
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Affiliation(s)
- J R Libonati
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, MA 02118, USA
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Bernstein EA, Eberli FR, Silverman AM, Horowitz GL, Apstein CS. Beneficial effects of felodipine on myocardial and coronary function during low-flow ischemia and reperfusion. Cardiovasc Drugs Ther 1996; 10:167-78. [PMID: 8842509 DOI: 10.1007/bf00823595] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An acute coronary occlusion causes severe low-flow ischemia in the occluded region. Calcium antagonists have the potential to reduce the rate of ischemic injury by decreasing myocardial oxygen demand, as well as by other mechanisms, especially when given prior to the onset of ischemia. However, their clinical use may be limited by their negative inotropic effects. The purpose of this study was to assess the effects of felodipine as a potentially protective agent against myocardial ischemia and reperfusion injury, independent of any negative inotropic actions, when given after the onset of low-flow ischemia. Isolated isovolumic (balloon-in-LV), blood-perfused rabbit hearts, paced at a constant heart rate, were subjected to 90 minutes of low-flow ischemia at a coronary perfusion pressure of 10 mmHg, which reduced coronary blood flow to 22-24% of baseline. After 15 minutes of low-flow ischemia, hearts received 2 x 10(-6) M felodipine (n = 7) or no drug (controls, n = 8). Felodipine was given until 15 minutes of reperfusion. During low-flow ischemia both groups of hearts had identical coronary blood flow, heart rate, left ventricular (LV) developed pressure, lactate production, and O2 consumption. However, felodipine markedly protected against ischemic diastolic dysfunction. At the end of low-flow ischemia, LV end-diastolic pressure (LVEDP) had increased from 10 +/- 1 to 28 +/- 5 mmHg in the felodipine group, while in the controls LVEDP increased to 48 +/- 8 mmHg (p < 0.05). During 30 minutes of reperfusion, felodipine had a beneficial effect upon coronary blood flow (initial postischemic hyperemia 245 +/- 38% of baseline in the felodipine group vs. 124 +/- 18% in the controls; p < 0.01) Felodipine markedly improved the recovery of contractile function [LV developed pressure recovered from a baseline of 104 +/- 4 to 75 +/- 6 mmHg (72%) in the felodipine group vs. 34 +/- 10 mmHg (32%) in the control group; p < 0.01], as well as diastolic function (LVEDP = 25 +/- 4 mmHg in the felodipine group vs. 61 +/- 10 mmHg in the controls; p < 0.05), and ATP levels (8.5 +/- 1.4 mumoles/g d.w. in the felodipine group vs. 3.9 +/- 1.4 mumoles/g d.w. in the control group, p < 0.05). Felodipine, given after the onset of low-flow ischemia, protects the myocardium during both ischemia and reperfusion by mechanisms other than reducing myocardial oxygen demand.
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Affiliation(s)
- E A Bernstein
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, MA, USA
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Libonati JR, Apstein CS, Ngoy S, Sesselberg H, Herrick B, Balady G, Dempsey A, Davidoff R, Eberli FR. EXERCISE TRAINING FOLLOWING MYOCARDIAL INFARCTION DOES NOT ADVERSELY AFFECT LEFT VENTRICULAR GEOMETRY OR FUNCTION. Med Sci Sports Exerc 1995. [DOI: 10.1249/00005768-199505001-00885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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50
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Affiliation(s)
- C S Apstein
- Cardiac Muscle Research Laboratory, Whitaker Cardiovascular Institute, Boston University School of Medicine, Massachusetts 02118, USA
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