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Impact of smoking habit on baseline and on-treatment platelet reactivity in STEMI patients treated with 3rd generation P2Y12. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Smoking habit is a well known risk factor for cardiovascular disease. High on-treatment platelet reactivity has been associated with high risk of ischemic events in STEMI patients. The relationship between platelet reactivity and smoking habit was investigated only in few studies, and the impact of smoke on platelet reactivity in STEMI patients treated with 3rd generation P2Y12 inhibitor is still lacking.
Purpose
This study aim to assess the impact of smoking habits on baseline and on-treatment platelet reactivity in STEMI patients treated with 3rd generation P2Y12 inhibitor.
Methods
Overall, 429 STEMI patients were enrolled in this study. Patients were divided into two groups according to smoking habit. Platelet reactivity was assessed by VerifyNow at baseline and after 3rd generation P2Y12 inhibitor (ticagrelor or prasugrel) loading dose (LD). Blood samples were obtained at baseline (T0), and after 1 hour (T1), 2 hours (T2), 4–6 hours (T3) and 8–12 hours (T4) after LD.
Results
The mean age of the enrolled population was 62±12 and male rate was 75%. Patients with smoking habit were younger (75.8% vs 38.9%, p<0.001 for age <65 years), with higher prevalence of family history of CAD, while with a lower rate hypertension (43.4% vs 65.9%, p<0.001) and previous myocardial infarction (5.3% vs 11.4%, p=0.022) (Table). Smoker patients had lower platelet reactivity either at baseline [T0: 249 (205–285) vs 284 (230–324), p<0.001] or at 2 hours after the LD [T2: 107 (18–279) vs 136 (51–260), p=0.003] (Table). Similarly, Smoker patients experienced a lower rate of in-hospital composite adverse event of death, reinfarction, stroke or acute kidney injury (1.6% vs 12.4%; p≤0.001) (Table). Multivariate analysis demonstrated that left ventricular ejection fraction at admission (OR= 0.916, 95% CI 0.865–0.969; p=0.002), and platelet reactivity at baseline (OR= 1.013, 95% CI 1.002–1.024; p=0.024) were independent predictors of in-hospital composite adverse event.
Conclusions
Smoker status is associated with lower platelet reactivity either at baseline or after LD and with a better short-term prognosis in STEMI patients treated by dual antiplatelet therapy with ticagrelor or prasugrel.
Funding Acknowledgement
Type of funding sources: None.
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P3580Impact of glucose-6-phosphate dehydrogenase deficiency on the extent and severity of coronary atherosclerosis in patients with acute coronary syndrome. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Studies in animal models and humans suggested that glucose-6-phosphate dehydrogenase (G6PD) deficiency, a genetically inherited condition causing haemolytic anemia, may be considered a risk factor for cardiovascular disease. It is currently unknown whether enzymatic activity may impact the extent and severity of coronary atherosclerosis in patients with acute myocardial infarction. This hypothesis was tested in a cohort of acute coronary syndrome (ACS) patients undergoing invasive management from Northern Sardinia, where the population prevalence of G6PD deficiency is the highest in the Mediterranean area.
Methods
The study was based on a prospective single-centre registry of consecutive ACS patients undergoing coronary angiography and subsequent percutaneous revascularization between January 2017 and December 2018, in which G6PD activity has been measured quantitatively using a biochemical assay based on G6PD/6GPD ratio in erythrocytes. Subjects were defined as deficient when the ratio was <0.80. The primary endpoint of the study was the severity of coronary artery disease as assessed by the SYNTAX I score at baseline angiography.
Results
Among the 466 enrolled patients, 41 (9%) showed G6PD deficiency. Patients with G6PD deficiency were less likely to have a history of dyslipidemia (27% vs 50%; p=0.005) or diabetes (12% vs 21%; p=0.105). As expected, at admission patients with deficiency had lower hemoglobin level (12.1 vs 13.7 g/dL; p=0.005) as compared with those without. By angiography, SYNTAX score resulted as 19±9 and 16±9 (p=0.039) in patients with and without G6PD deficiency; while the number of diseased (with >50% stenosis) vessels was 1.9 vs 1.6 (p=0.089) in the 2 study groups. Left main disease was detected in 15% and 7% (p=0.06) patients, respectively. G6PD deficiency emerged as an independent predictor of high SYNTAX score (OR=2.16, 95% CI 1.1–4.5; p=0.037). Angioplasty with coronary stenting of the culprit vessel was performed in all patients, while GP IIb/IIIa inhibitors were used in 30% and 14% (p=0.009) of patients with and without G6PD deficiency. Finally, in-hospital events were similar between the 2 study groups.
Conclusions
An increased extent and severity of coronary artery disease was observed in ACS patients with G6PD deficiency as compared with those without, despite the lower prevalence of “classic” cardiovascular risk factors.
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Abstract
Aging of the vasculature results in arterial stiffening and an increase in systolic and pulse pressures. Although pressure load is a stimulus for left ventricular hypertrophy, the extent to which vascular stiffening per se, independent of blood pressure, influences left ventricular structure is uncertain. Two hundred seventy-six subjects (79 normotensive and 197 otherwise healthy hypertensive individuals) underwent echocardiography to assess left ventricular structure. Arterial stiffness was estimated by the pressure-independent stiffness index, beta, and the pressure-dependent elastic modulus derived from simultaneous carotid ultrasound and applanation tonometry. Systemic arterial compliance (the inverse of stiffness) was estimated by the arterial compliance index. In multivariate analysis, beta was related to age (P<0.001) and smoking history (P<0.01) but not mean pressure, whereas elastic modulus was related to age and mean pressure (both P<0.001). The arterial compliance index was only related to age. Whereas systolic and diastolic pressures and the elastic modulus were positively associated with left ventricular mass (all P<0.001), primarily because of increases in wall thicknesses, beta and the arterial compliance index bore no relation to left ventricular mass. beta was inversely related to chamber diameter and directly related to left ventricular relative wall thickness, the ratio of wall thickness to chamber radius. Younger and older hypertensive subjects had comparable left ventricular mass, despite higher systolic and pulse pressures in the older group, whereas older hypertensives had higher mean relative wall thickness, associated with a significant increase in arterial stiffness (beta, 7.06 versus 5.17; elastic modulus, 595 versus 437 dyne/cm(2) x10(-6)) and reduction in the arterial compliance index (0.87 versus 1.05 mL/mm Hg per square meter) (all P<0.001). Thus, the extent to which arterial stiffness relates to left ventricular hypertrophy is dependent on the method by which arterial stiffness is estimated. Pressure-dependent methods show an association with left ventricular hypertrophy, whereas the pressure-independent stiffness index, beta, and the arterial compliance index are most strongly associated with aging and left ventricular concentric remodeling but not hypertrophy.
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Carotid intimal-medial thickness and stiffness are not affected by hypercholesterolemia in uncomplicated essential hypertension. Arterioscler Thromb Vasc Biol 1999; 19:2788-94. [PMID: 10559027 DOI: 10.1161/01.atv.19.11.2788] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The combined effects of hypertension and hypercholesterolemia on carotid anatomy and stiffness were studied in 62 normotensives, 141 uncomplicated essential hypertensives with a total cholesterol level <240 mg/dL, and 60 essential hypertensives with a total cholesterol level >/=240 mg/dL. Carotid ultrasonography was performed to evaluate intimal-medial thickness (IMT), relative wall thickness, and the presence of plaque. Carotid pressure waveforms were recorded by applanation tonometry to measure carotid stiffness (beta) and pressure wave reflection (ie, augmentation index). After adjusting for age, body mass index, and smoking habit by analysis of covariance, no significant differences were found between normocholesterolemic hypertensives and hypercholesterolemic hypertensives in terms of IMT (0.79+/-0.19 versus 0.81+/-0.19 mm), relative wall thickness (0.27+/-0.07 versus 0.28+/-0.07), carotid stiffness (6.1+/-3.2 versus 5.6+/-2.7), augmentation index (18. 7+/-12.9% versus 17.3+/-12.8%), and prevalence of plaque (30.8% versus 30.7%). In the whole population, carotid IMT was significantly related to age (r=0.43), systolic (r=0.35) and diastolic (r=0.35) blood pressures, body surface area (r=0.22), and cholesterol levels (r=0.22) (all P<0.05). Carotid stiffness was significantly related to age, blood pressure, body mass index, and body surface area but not to cholesterol levels. In multivariate analyses, age, body surface area, and systolic blood pressure, but not cholesterol, smoking habit, or sex, were independent correlates of IMT (multiple R=0.54, P<0.0001), whereas carotid stiffness was independently associated with age, body surface area, and sex (R=0. 38, P<0.0001). In conclusion, hypertension is a potent stimulus of vascular hypertrophy. The superimposition of hypercholesterolemia does not substantially augment these changes or further increase arterial stiffness in uncomplicated hypertensive subjects.
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Abstract
OBJECTIVE Effective arterial elastance (Ea), integrating the pulsatile component of left ventricular (LV) afterload, is an estimate of aortic input impedance. We evaluated relationships of Ea with left ventricular anatomy and function in essential hypertension. DESIGN A cross-sectional analysis in 81 normotensive and 174 untreated hypertensive individuals enrolled in a referral hypertension centre. METHODS Using echocardiography we determined left ventricular mass index (LVMI), relative wall thickness (RWT), stroke volume (SV), endocardial (FSe) and midwall (FSm) fractional shortening and total peripheral resistance (TPR). Carotid pressure waveforms were obtained by arterial tonometry, and end-systolic pressure (Pes) was measured at the dicrotic notch. Ea index (EaI) was calculated as Pes/(SV index); LV elastance (Ees) was estimated as Pes/LV end-systolic volume, and ventriculo-arterial coupling was evaluated by the Ea/Ees ratio. RESULTS EaI was higher in hypertensives than in normotensives (3.02 +/- 0.63 versus 2.40 +/- 0.52 mmHg/l per m2; P< 0.0001). Using the 95% upper confidence limit in normotensives, hypertensives were divided in two groups with normal or elevated EaI. The 38 hypertensives with elevated EaI had higher RWT (0.41 +/- 0.06 versus 0.37 +/- 0.05), lower LVMI (87.5 +/- 18.5 versus 96.8 +/- 19.3 g/m2), higher TPR (2247 +/- 408 versus 1658 +/- 371 dynes/cm s(-5)) and lower FSe and FSm (35 +/- 5 versus 39 +/- 5 and 16 +/- 2 versus 18 +/- 2%; all P< 0.05) than patients with normal EaI. Ea/Ees ratio was increased and cardiac output was reduced in hypertensives with elevated EaI. CONCLUSIONS High values of EaI identify a minority of hypertensive patients characterized by elevated TPR, left ventricular concentric remodelling, depressed left ventricular systolic function and impaired ventriculo-arterial coupling.
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Abstract
The extent to which age, independent of cardiovascular diseases, influences left ventricular (LV) function in adults is uncertain. Echocardiograms and simultaneous arterial pressure in 464 clinically normal adults aged 16 to 88 years were used to measure LV dimensions, endocardial and midwall LV fractional shortening, stroke volume, cardiac output, and circumferential end-systolic stress. The ratios of observed endocardial and midwall shortening to values predicted for observed end-systolic stress were used as measures of chamber and myocardial function. LV endocardial shortening increased slightly with age, as did an index of LV chamber performance, the end-systolic stress/volume index ratio (r = 0.11, p = 0.019, and r = 0.20, p <0.001). However, when age-related increases in LV wall thickness and blood pressure were controlled for by examining afterload-corrected endocardial shortening, no age relation was detected. Weak age-related declines were observed in midwall shortening (r = -0.09, p = 0.043) and afterload-corrected midwall shortening (r = -0.12, p <0.01). Cardiac index decreased slightly with advancing age (r = -0.14, mean -6.7 ml/min/m2/ year, p = 0.003). Total peripheral resistance and the pulse pressure/stroke volume ratio, a measure of arterial stiffness, increased more strongly with age (r = 0.27 and 0.38, both p <0.001). Thus, LV pump performance at rest measured by cardiac index is slightly lower in older than in younger clinically normal adults. Endocardial fractional shortening was slightly higher in older subjects, but the physiologically more appropriate midwall measures of myocardial function decreased slightly. The observed change in LV pump performance was related to smaller LV chamber size and higher total peripheral resistance in older subjects.
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Left ventricular hypertrophy, arterial compliance, and aging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1998; 432:13-22. [PMID: 9433507 DOI: 10.1007/978-1-4615-5385-4_2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Estimation of left ventricular chamber and stroke volume by limited M-mode echocardiography and validation by two-dimensional and Doppler echocardiography. Am J Cardiol 1996; 78:801-7. [PMID: 8857486 DOI: 10.1016/s0002-9149(96)00425-0] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This study has been designed to improve estimation of stroke volume from linear left ventricular (LV) dimensions measured by M-mode echocardiography, in symmetrically contracting ventricles. In experimental studies, the ratio of LV epicardial long/short axes "Z" is about 1.3. We measured systolic and diastolic epicardial long and short axes by 2-dimensional echocardiography in 115 adults with widely varying LV short-axis dimensions (LV end-diastolic dimension = 3.95 to 8.3 cm). In a learning series of 23 normotensive and 27 hypertensive subjects, Z(diastole) was 1.3 +/- 0.1 and Z(systole) = 1.2 +/- 0.1, similar to findings in experimental animals. Regression equations were developed by comparing LV volumes by M-mode and 2-dimensional echocardiography. In a test series (65 subjects), LV volumes were calculated using separate regression equations for end-diastolic volume ([LV end-diastolic dimension] 4.765 - 0.288 x posterior wall thickness]) and for end-systolic volume ([LV end-systolic dimension] [4.136 - 0.288 x posterior wall thickness]). Because the term 0.288 x wall thickness was only about 8% of the first term between brackets, the average wall thickness in the learning series was substituted in the Z-volume formulas applied to the test series: end-diastolic volume = (4.5 x [LV end-diastolic dimensions]2) and end-systolic volume = (3.72 x [LV end-diastolic dimension]2). The mean relative error produced with this simplified method was 0.9%. in diastole and 1.4% in systole. Compared with Teichholz' M-mode volume method, Z-derived end-diastolic volume in the test series was equally well related to 2-dimensional volumes (both r = 0.88), with a better intercept (1.5 vs -23 ml, p <0.001) and a slope closer to the identity line (1.1 vs 1.4). Similar results were found for systolic volumes. In a second test series of 1,721 American Indian participants in the Strong Heart Study without mitral regurgitation or segmental LV wall motion abnormalities, Doppler-derived LV stroke volume (70 +/- 14 ml/beat) was similarly predicted by the Z-derived method (r = 0.65, 70 +/- 11 ml/beat) and Teichholz formulas (r = 0.64, 72 +/- 13 ml/beat), but Z-derived volumes had a regression line significantly closer to the identity line (p <0.005). Thus, LV chamber and stroke volumes can be determined from M-mode LV diameters over a wide range of LV sizes and in epidemiologic as well as clinical populations. The performance of this new method appears better than that obtained using the Teichholz formula, with a formula that is easy to handle and makes calculation of LV volumes by pocket calculator possible, even from limited echocardiographic studies.
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Ageing induces left ventricular concentric remodelling in normotensive subjects. J Hypertens 1995; 13:1818-22. [PMID: 8903659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess whether age affects left ventricular anatomy independently of age-related hypertension or concomitant heart diseases. DESIGN AND METHODS In 430 consecutive normotensive and clinically healthy subjects aged 16-85 years we obtained echocardiographic measurements of left ventricular posterior wall thickness, internal diameter, relative wall thickness, Penn mass index and systemic haemodynamics. The pulse pressure : stroke volume ratio was calculated as an estimate of systemic arterial stiffness. The subjects were divided into three age groups: < or = 40 (group 1, n = 137), 41-64 (group 2, n = 261) and > or = 65 years (group 3, n = 32). RESULTS Systolic blood pressure increased from group 1 to group 3, as did the pulse pressure : stroke volume ratio and posterior wall thickness, whereas the left ventricular internal diameter was less in group 3 than in groups 1 and 2. The relative wall thickness increased from group 1 to groups 2 and 3, whereas the left ventricular mass index did not differ among age groups. Age was related positively to the systolic blood pressure, pulse pressure : stroke volume ratio, posterior wall thickness index and relative wall thickness, and negatively to the left ventricular internal diameter but not to the left ventricular mass index. CONCLUSIONS In healthy adults, relative wall thickness increases with age whereas left ventricular mass does not change. The concentric remodelling of left ventricular geometry parallels age-related stiffening of the arterial tree, elevation of systolic blood pressure and decrease in left ventricular volume. Thus partition values of relative wall thickness should be adjusted for age.
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The effect of midazolam on left ventricular pump performance and contractility in anesthetized patients with coronary artery disease: effect of preoperative ejection fraction. Anesth Analg 1995; 81:793-9. [PMID: 7574012 DOI: 10.1097/00000539-199510000-00023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Forty patients undergoing coronary artery bypass grafting were studied, of whom 24 had depressed global left ventricular (LV) function at preoperative catheterization, to evaluate the effects of midazolam on LV pump performance and contractility. Transesophageal echocardiography and simultaneous hemodynamic measurements were used to assess LV preload, afterload, and systolic performance during inhalation of 100% O2 and after 0.1 mg/kg of midazolam. Systolic function indices were expressed as a percent of the predicted value for observed end-systolic stress to estimate LV contractility. In the entire study population, midazolam did not affect cardiac index. Heart rate and mean arterial pressure were reduced (63 +/- 13 to 59 +/- 12 bm; P < 0.0006 and 89 +/- 15 to 76 +/- 16 mm Hg; P < 0.0001) as were pulmonary capillary wedge pressure, central venous pressure, and systemic and pulmonary vascular resistance. Afterload, as measured by end-systolic stress, was reduced (55 +/- 33 to 48 +/- 26 kdyne/cm2; P = 0.007) with no change in fractional shortening or percent area change. As a result, systolic function decreased in relation to observed end-systolic stress, providing evidence of reduced LV contractility. Thus, midazolam administration (0.1 mg/kg) caused no change in cardiac pump performance but decreased LV contractility in the entire population. Myocardial contractility was lower at baseline and after the administration of midazolam in the depressed ejection fraction group, but the decrease in contractility was not exaggerated in the depressed ejection fraction group.(ABSTRACT TRUNCATED AT 250 WORDS)
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Relationship of effective arterial elastance to demographic and arterial characteristics in normotensive and hypertensive adults. J Hypertens 1995; 13:971-7. [PMID: 8586832 DOI: 10.1097/00004872-199509000-00006] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To evaluate demographic and vascular correlates of the effective arterial elastance noninvasively in normotensive and hypertensive adults. METHODS In 202 subjects carotid ultrasonography and external arterial tonometry were simultaneously performed; carotid cross-sectional area, absolute and relative wall thicknesses, Peterson's and Young's elastic moduli and beta', a pressure-dependent index of arterial stiffness, were calculated. The impact of reflected waves on central pressure waveforms was evaluated by the 'augmentation index' (the relative increment in systolic pressure caused by the late-systolic peak). Left ventricular mass and relative wall thickness were assessed echocardiographically. The effective arterial elastance was estimated by dividing the pressure at the dicrotic notch by the Doppler-determined stroke index. RESULTS The effective arterial elastance was higher in women among normotensives but similar between sexes among hypertensive subjects. It was correlated to age, mean blood pressure, body mass index and measures of arterial function, including Peterson's and Young's elastic moduli and beta', and to the augmentation index. It was also related to absolute and relative carotid wall thicknesses, lumen diameter and indexed cross-sectional area. Age, beta' and carotid cross-sectional area independently predicted effective arterial elastance in multiple regression analysis. CONCLUSIONS Effective arterial elastance is related to demographic and arterial structural and functional characteristics. Increases in effective arterial elastance resulting from altered arterial structure and function may play a role in inducing left ventricular adaptative modifications.
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Assessment of left ventricular function by the midwall fractional shortening/end-systolic stress relation in human hypertension. J Am Coll Cardiol 1994; 23:1444-51. [PMID: 8176105 DOI: 10.1016/0735-1097(94)90390-5] [Citation(s) in RCA: 457] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVES This study examined left ventricular performance in relatively unselected hypertensive patients by use of physiologically appropriate midwall shortening/end-systolic stress relations. BACKGROUND Supranormal left ventricular function has been reported in hypertensive patients, possibly due to an artifact of mismatching endocardial rather than midwall fractional shortening to mean left ventricular end-systolic stress. METHODS Samples of 474 hypertensive patients (150 women, 324 men) and 140 normal subjects (68 women, 72 men) were drawn from a large urban employed population. The inverse relations (p < 0.0001) of both echocardiographic endocardial and midwall fractional shortening to end-systolic stress in normal subjects were used to calculate the ratios of observed to predicted endocardial and midwall fractional shortening in hypertensive patients. Midwall shortening was calculated from an elliptic model, taking into account the epicardial migration of the midwall during systole. RESULTS Use of midwall fractional shortening in hypertensive patients reduced the proportion of patients with function above the 95th percentile of normal from 22% to 4% (p < 0.0001) and fractional shortening as a percent of predicted from 107% (p < 0.001 vs. 100% in normotensive control subjects) to 95% (p < 0.0001; p < 0.001 vs. 101% in normotensive control subjects). Midwall shortening was below the 5th percentile of normal in 16% of hypertensive patients instead of 2% with endocardial shortening (p < 0.0001): They tended to be older than other hypertensive patients and had concentric left ventricular hypertrophy. Among hypertensive patients, those with concentric left ventricular hypertrophy or remodeling had reduced midwall shortening as a percent of predicted from end-systolic stress (p < 0.0001). CONCLUSIONS Use of the physiologically more appropriate midwall shortening/end-systolic stress relation 1) markedly reduces the proportion of hypertensive subjects identified as having high endocardial left ventricular function; and 2) identifies a substantial subgroup of patients with reduced left ventricular function who have concentric geometry of the left ventricle, a pattern associated with high cardiovascular risk.
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Abstract
OBJECTIVES The purpose of this study was to examine the relation of the central arterial pressure waveform to left ventricular and carotid structure. BACKGROUND The pressure waveform in the central arteries is affected by reflection of the pressure wave from the periphery. When reflected waves merge with the incident wave during systole, a late systolic peak and increment in systolic blood pressure are observed. The consequent increase in hemodynamic load may stimulate left ventricular and vascular adaptive changes. METHODS Sixty-seven normotensive adults were studied by noninvasive techniques. Anatomy and function of the left ventricle and carotid artery were investigated by ultrasonography. Pressure waveforms were recorded by an external tonometer applied to the carotid artery, and waveform shape was expressed by the augmentation index, calculated from the difference between the maximal systolic pressure and that at the inflection between early and late systolic pressure peaks divided by the pulse pressure. Subjects were assigned to groups with a dominant early (group 1, augmentation index < or = 0) or dominant late systolic peak (group 2, augmentation index > 0). RESULTS Left ventricular mass index was significantly higher in group 2 than in group 1, a difference that persisted after controlling for the confounding effects of gender, age and blood pressure. Carotid wall thickness and regional arterial stiffness were significantly increased in group 2, but differences disappeared in the analysis of covariance for age. CONCLUSIONS Left ventricular and carotid artery structure are related to the shape of the central pressure waveform. Although the increase in left ventricular mass seen in subjects with a dominant late systolic peak pressure appears to be directly related to the shape of the pressure waveform, changes in the structural and physical properties of the carotid artery appear to be more closely related to the aging process.
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The effect of nitrous oxide on left ventricular pump performance and contractility in patients with coronary artery disease: effect of preoperative ejection fraction. Anesth Analg 1993; 77:954-62. [PMID: 8214734 DOI: 10.1213/00000539-199311000-00015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To elucidate the effects of nitrous oxide (N2O) on left ventricular (LV) pump performance and contractility, 28 patients undergoing coronary artery bypass graft surgery were studied, of whom 15 had depressed global LV function at preoperative catheterization. Transesophageal echocardiography and simultaneous hemodynamic measurements were used to assess LV preload, afterload, and systolic performance during inhalation of 100% oxygen (O2) and 60% N2O:40% O2. Systolic function indices were expressed as a percent of the predicted value for observed end-systolic stress to provide estimates of LV contractility. In the entire study population, N2O reduced pump performance (cardiac index 2.4 +/- 0.8 to 2.2 +/- 0.6 L.min-1 x m-2; P < 0.02). Heart rate and mean arterial pressure were reduced (67 +/- 13 to 64 +/- 13, P < 0.01, and 87 +/- 9 to 80 +/- 15, P < 0.005) as were left and right ventricular stroke work index. Preload, as measured by end-diastolic stress, was unchanged but afterload, as measured by end-systolic stress, tended to decrease (88 +/- 31 to 78 +/- 28, P = 0.053). In the 13 patients with normal preoperative LV function, mean arterial pressure and LV stroke work index decreased significantly (91 +/- 8 to 84 +/- 14, P < 0.04, and 40 +/- 13 to 34 +/- 10, P < 0.04, respectively) and end-systolic stress tended to decrease (P = 0.054).(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
BACKGROUND Although vascular damage in the noncoronary circulation is a major cause of complications in hypertension, relatively little is known of the in vivo geometry and function of the arterial circulation in patients with uncomplicated hypertension or of their relation to left ventricular hypertrophy, a marker of enhanced risk of cardiovascular complications. METHODS AND RESULTS Wall thickness and internal diameter of the common carotid artery and the presence of atherosclerosis within the extracranial carotid arteries were determined by ultrasound in 43 asymptomatic hypertensive patients and 43 normotensive subjects matched for sex, age, and body size. Vascular stiffness was estimated from simultaneous superimposed carotid pressure waveforms obtained with an external solid-state transducer. Left ventricular size and function were determined echocardiographically. Compared with normal subjects, hypertensive patients had greater left ventricular absolute and relative wall thicknesses, left ventricular mass, and carotid absolute and relative wall thicknesses (p < 0.005). Carotid intimal-medial thickness exceeded the 95th percentile of normal values in 28% of hypertensive patients (p < 0.01). Carotid atherosclerosis was equally prevalent within the two blood pressure groups and was associated with older age, larger left ventricular and carotid wall thicknesses, and carotid diameter. Despite similar carotid pulse pressures, vascular stiffness was significantly increased in the hypertensive patients. Among the population as a whole, significant relations existed between cardiac and vascular wall thicknesses and internal dimensions. In multivariate analyses, these relations were statistically independent of age and blood pressure. CONCLUSIONS The present study documents the presence of geometric and functional changes within the common carotid artery in uncomplicated hypertension that parallel findings within the left ventricle. The potential contribution of these changes to the cardiovascular complications of hypertension, particularly in the setting of left ventricular hypertrophy, is unknown.
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Abstract
The spectrum of left ventricular geometric adaptation to hypertension was investigated in 165 patients with untreated essential hypertension and 125 age- and gender-matched normal adults studied by two-dimensional and M-mode echocardiography. Among hypertensive patients, left ventricular mass index and relative wall thickness were normal in 52%, whereas 13% had increased relative wall thickness with normal ventricular mass ("concentric remodeling"), 27% had increased mass with normal relative wall thickness (eccentric hypertrophy) and only 8% had "typical" hypertensive concentric hypertrophy (increase in both variables). Systemic hemodynamics paralleled ventricular geometry, with the highest peripheral resistance in the groups with concentric remodeling and hypertrophy, whereas cardiac index was super-normal in those with eccentric hypertrophy and low normal in patients with concentric remodeling. The left ventricular short-axis/long-axis ratio was positively related to stroke volume (r = 0.45, p less than 0.001), with cavity shape most elliptic in patients with concentric remodeling and most spheric in those with eccentric hypertrophy. Normality of left ventricular mass in concentric remodeling appeared to reflect offsetting by volume "underload" of the effects of pressure overload, whereas eccentric hypertrophy was associated with concomitant pressure and volume overload. Thus, arterial hypertension is associated with a spectrum of cardiac geometric adaptation matched to systemic hemodynamics and ventricular load. Concentric left ventricular remodeling and eccentric hypertrophy are more common than the typical pattern of concentric hypertrophy in untreated hypertensive patients.
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Stroke volume and left heart anatomy in relation to plasma volume in essential hypertension. JOURNAL OF HYPERTENSION. SUPPLEMENT : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF HYPERTENSION 1991; 9:S150-1. [PMID: 1818920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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