Stent implantation in acute myocardial infarction using a heparin-coated stent: a pilot study as a preamble to a randomized trial comparing balloon angioplasty and stenting

Preliminary experience with primary stenting in myocardial infarction has suggested a greater benefit in clinical outcome than has been obtained with direct balloon angioplasty. However, subacute thrombosis (SAT) remains a limitation for this new mode of therapy. In the BENESTENT II Pilot and main trials, the incidence of SAT with the heparin-coated Palmaz-Schatz stent was only 0.15%. Therefore, as a preamble to a large randomized trial, the feasibility and safety of the use of the Heparin-Coated Palmaz-Schatz trade mark Stent in Acute Myocardial Infarction (AMI) was tested in 101 patients enrolled between April and September 1996 in 18 clinical centres. In 101 stent-eligible AMI patients, as dictated by protocol, a heparin-coated stent was implanted. The primary objectives were to determine the in-hospital incidence of major adverse cardiac events (MACE: death, MI, target lesion revascularization) and bleeding complications, while the secondary objectives were the procedural success rate and the MACE, the restenosis and reocclusion rates at 6.5 months. Stent implantation (n 3 129 stents) was successful in 97 patients of the 101 who were included in this trial. During their hospital stay, two patients died and no patient experienced re-infarction, ischaemia prompting re-PTCA or CABG. Four patients suffered a bleeding complication, three major and one minor, of whom three required surgical repair. At 210 days follow-up, 81% of the patients were event free. At 6.5 months restenosis was documented in 18% of the 88 patients who underwent follow-up angiography, including three total occlusions. The results, both with respect to QCA and the occurrence of MACE, compare favourably with studies using elective stenting in both stable and unstable angina patients. As a result of this pilot study, a large randomized trial comparing direct balloon angioplasty with direct stenting in 900 patients with AMI was initiated in December 1996.

Intracoronary beta-radiation to reduce restenosis after balloon angioplasty and stenting; the Beta Radiation In Europe (BRIE) study

AIMS

The BRIE trial is a registry evaluating the safety and performance of (90)Sr delivered locally (Beta-Cath TM system of Novoste) to de-novo and restenotic lesions in patients with up to two discrete lesions in different vessels.

METHODS AND RESULTS

In total, 149 patients (175 lesions) were enrolled; 62 treated with balloons and 113 with stents. The restenosis rate, the minimal luminal diameter and the late loss were determined in three regions of interest: (a) in a subsegment of 5mm containing the original minimal luminal diameter pre-intervention termed target segment; (b) the irradiated segment, 28 mm in length, and (c) the entire analysed segment, 42 mm in length, termed the vessel segment. Binary restenosis was 9.9% for the target segment, 28.9% for the irradiated segment, and 33.6% for the vessel segment. These angiographic results include 5.3% total occlusions. Excluding total occlusions binary restenosis was 4.9%, 25% and 29.9%, respectively. At 1 year the incidence of major adverse cardiac events placed in a hierarchical ranking were: death 2%, myocardial infarction 10.1%, CABG 2%, and target vessel revascularization 20.1%. The event-free survival rate was 65.8%. Non-appropriate coverage of the injured segment by the radioactive source termed geographical miss affected 67.9% of the vessels, and increased edge restenosis significantly (16.3% vs 4.3%, P=0.004). It accounted for 40% of the treatment failures.

CONCLUSION

The results of this registry reflect the learning process of the practitioner. The full therapeutic potential of this new technology is reflected by the restenosis rate at the site of the target segment. It can only be unravelled once the incidence of late vessel occlusion and geographical miss has been eliminated by the prolonged use of thienopyridine, the appropriate training of the operator applying this new treatment for restenosis prevention, and the use of longer sources.

The ARTS study (Arterial Revascularization Therapies Study)

The rising costs of health care have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that stenting has a major and long-lasting effect enhancing balloon PTCA procedure has made it imperative to compare in patients with multivessel disease the standard surgical procedure with multiple stenting in a large scale multinational and multicentre approach (19 countries, 68 sites). Selection and inclusion of patients is based on a consensus of the cardiac surgeon and interventional cardiologist on equal 'treatability' of patients by both techniques with analysis of clinical follow-up (event-free survival) on the short (30 day), medium (1 year), and long-term (3 and 5 year) with analysis of cost-effectiveness and quality of life (EuroQol and SF-36). Of the entire trial, the primary null hypothesis which needs to be rejected is that there will be no difference in event-free survival or effectiveness (E), at 1 year and also that the direct and indirect costs (C) per event-free year are not different between surgery or stenting. For this to become significant with a power of 90% one needs 1200 patients. Between April 97 and June 98, 1205 patients have been randomized with a monthly recruitment of 83 patients. Expected costs, effects and cost-effectiveness ratio (CE ratio) are: Stent high costs 2 VDStent high costs 3 VDStent low costs 2 VDStent low costs 3 VDCABG costs (C)$19.297$24.566$16.638$20.456$21.350 effects (E)81%81%81%81%88% CE ratio$23.876$30.397$20.586$25.322$24.348 Clinically, stenting is not expected to be more effective than CABG, but should be cost effective in both the 2- and 3-VD group when using the lower cost estimate and in the 2 VD group when using the higher cost assumptions.

Randomized comparison of angioplasty of complex coronary lesions at a single center. Excimer Laser, Rotational Atherectomy, and Balloon Angioplasty Comparison (ERBAC) Study

BACKGROUND

The purpose of this study was to test whether coronary revascularization with ablation of either excimer laser or rotational atherectomy can improve the initial angiographic and clinical outcomes compared with dilatation (balloon angioplasty) alone.

METHODS AND RESULTS

At a single center, a total of 685 patients with symptomatic coronary disease warranting elective percutaneous revascularization for a complex lesion were randomly assigned to balloon angioplasty (n = 222), excimer laser angioplasty (n = 232), or rotational atherectomy (n = 231). The primary end point was procedural success (diameter stenosis < 50%, absence of death, Q-wave myocardial infarction, or coronary artery bypass surgery). The patients who underwent rotational atherectomy had a higher rate of procedural success than those who underwent excimer laser angioplasty or conventional balloon angioplasty (89% versus 77% and 80%, P = .0019), but no difference was observed in major in-hospital complications (3.2% versus 4.3% versus 3.1%, P = .71). At the 6-month follow-up, revascularization of the original target lesion was performed more frequently in the rotational atherectomy group (42.4%) and the excimer laser group (46.0%) than in the angioplasty group (31.9%, P = .013).

CONCLUSIONS

Procedural success of rotational atherectomy is superior to laser angioplasty and balloon angioplasty; however, it does not result in better late outcomes. The role of plaque debulking before balloon dilatation in percutaneous coronary revascularization remains to be fully defined.

Prospective case-control comparison of percutaneous transluminal coronary revascularization in patients with multivessel disease treated in 1986-1987 versus 1991: improved in-hospital and 12-month results. Multivessel Angioplasty Prognosis Study (MAPS) Group

OBJECTIVES

This study sought to ascertain whether early and 12-month clinical outcomes after percutaneous coronary revascularization have improved between 1986-1987 and 1991.

BACKGROUND

Since the mid-1980s, when the results of percutaneous revascularization were considered to be somewhat static, justifying large-scale clinical trials of percutaneous transluminal coronary angioplasty versus other modes of therapy, balloon technology has improved, and several new percutaneous revascularization techniques have become available. The clinical results of the current integrated approach to revascularization compared with those for coronary angioplasty alone in the late 1980s are not known.

METHODS

In this prospective case-control study, 200 consecutively treated patients with multivessel disease in 1991 were studied prospectively and compared with 400 consecutive patients from the same centers during 1986-1987. Patients from 1991 were matched with earlier patients on the basis of four previously described prognostic determinants (left ventricular ejection fraction, presence of unstable angina, diabetes and target lesion morphology score) and the treating institution and were assessed for treatment outcome (completeness of revascularization, procedural success and event-free survival [freedom from death, myocardial infarction and further revascularization]).

RESULTS

The 1991 cohort of patients was older (mean [+/- SD] age 62 +/- 11 vs. 58 +/- 11 years, p < 0.001) and tended to have slightly worse left ventricular function (ejection fraction 56 +/- 10% vs. 58 +/- 11%, p = 0.009) than the 1986-1987 cohort. Overall lesion morphology risk scores were similar. New devices (other than coronary angioplasty) were used in 26% of patients. The 1991 patient cohort had more frequent total revascularization (35% vs. 21%, p = 0.003), fewer emergency bypass operations (1.0% vs. 5.5%, p = 0.006) and an improved overall procedural success rate (90% vs. 84%, p = 0.04). In addition, at 12 months the event-free survival rate was superior in the 1991 cohort (73.3% vs. 63.6%, p = 0.02), although there was no difference in infarct-free survival rate (94.6% vs. 93.2%, p = NS).

CONCLUSIONS

Improved results with percutaneous revascularization in 1991 have important implications for patient care and interpretation of ongoing randomized trials enrolling patients in the late 1980s and intending to compare standard coronary angioplasty with other forms of therapy.

Randomized trial comparing two devices: the Palmaz-Schatz stent and the Strecker stent in bail-out situations

To assess whether differences in design (geometry, flexibility) and material (electrostatic behavior) may influence the acute and late outcome following intracoronary stent implantation in the treatment of acute or threatened closure after prolonged balloon inflations, 50 patients were randomized to receive either a Palmaz-Schatz stent (n = 25) or a Strecker stent (n = 25).

RESULTS

[table: see text]

CONCLUSION

Both Palmaz-Schatz and Strecker stents are equally effective in restoring vessel patency in bail-out situations. The incidence of complications is high and similar for both stents if they were used after failed prolonged balloon inflations. Differences in design and material do not seem to influence the results.

A randomized trial of late reperfusion therapy for acute myocardial infarction. Thrombolysis and Angioplasty in Myocardial Infarction-6 Study Group

BACKGROUND

Experimental and observational clinical studies of acute coronary occlusion have suggested that late reperfusion prevents infarct expansion and facilitates myocardial healing. The purpose of this trial was to assess whether infarct vessel patency could be achieved in late-entry patients and what benefit, if any, can be demonstrated.

METHODS AND RESULTS

In a double-blind fashion, 197 patients with 6 to 24 hours of symptoms and ECG ST elevation were randomly assigned to tissue-type plasminogen activator (100 mg over 2 hours) or placebo. Coronary angiography within 24 hours was used to determine infarct vessel patency status. Patients with infarct-related occluded arteries were then eligible for a second randomization to either angioplasty (34 patients) or no angioplasty (37 patients). Ventricular function and cavity size were reassessed at 1 month by gated blood pool scintigraphy and at 6 months by repeat cardiac catheterization. The primary end point, infarct vessel patency, was 65% for plasminogen activator patients compared with 27% in the placebo group (p less than 0.0001). There were no differences between these groups in ejection fraction or infarct zone regional wall motion at 1 or 6 months. At 6 months, infarct vessel patency was 59% in both groups. In the placebo group, there was a significant increase in end-diastolic volume from acute phase of 127 ml to 159 ml at 6-month follow-up (p = 0.006) but no increase in cavity size for the plasminogen activator group patients. Coronary angioplasty was associated with an initial 81% recanalization success and improved ventricular function at 1 month, but by late follow-up no advantage could be demonstrated for this procedure, and there was a 38% spontaneous recanalization rate in the patients assigned to no angioplasty.

CONCLUSIONS

The study demonstrates that it is possible to achieve infarct vessel recanalization in the majority of late-entry patients with either thrombolytic therapy or angioplasty. Thrombolytic intervention had a favorable effect on prevention of cavity dilatation and left ventricular remodeling, but there are no late benefits on systolic function after thrombolysis or coronary angioplasty. The conclusions concerning overall potential benefit of applying late reperfusion therapy will require data from large-scale trials designed to assess mortality reduction.

Predictors of long-term cardiac survival in patients with multivessel coronary artery disease undergoing percutaneous transluminal coronary angioplasty

The predictors of 5-year cardiac survival in patients with multivessel coronary artery disease (CAD) undergoing percutaneous transluminal coronary angioplasty (PTCA) were analyzed in a series of 637 consecutive patients. The average age was 59 +/- 11 years in 472 men and 165 women. Diabetes mellitus, previous myocardial infarction and unstable angina were present in 119 (19%), 261 (41%) and 305 (47%) patients, respectively. Angiographically, 460 patients had 2-vessel and 177 patients had 3-vessel CAD. The left ventricular contraction score was greater than or equal to 12 in 55 patients. Angiographic success (less than 50% residual stenosis) was achieved in 85% of the 1,343 narrowings and clinical success was obtained in 526 (83%) of the 637 patients. Complete revascularization was obtained in 177 (34%) of 526 successful patients. Procedure-related complications resulted in death in 9 patients (1.4%), in Q-wave myocardial infarction only in 6 patients (0.9%) and in emergency bypass surgery in 44 patients (6.9%) (of whom 10 had Q-wave myocardial infarction). Follow-up for greater than or equal to 1 year and up to 6 years after PTCA was obtained in 608 (95%) of the 637 patients. To determine the predictors of 5-year cardiac survival, 28 clinical, angiographic and procedural variables were analyzed by Cox proportional-hazards regression. The estimated 5-year survival after PTCA was 88 +/- 2% in successful patients and 77 +/- 5% in patients in whom PTCA was unsuccessful (p less than 0.001). When clinical success was forced into the Cox regression, the left ventricular contraction score of greater than or equal to 12, diabetes mellitus and age greater than or equal to 65 years showed additional adverse effects on survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Attenuation of pulsus alternans during coronary angiography

Following coronary angiography in a patient with cardiomyopathy and pulsus alternans, we observed a transient but marked attenuation of the alternation in pulse pressure associated with an elevation in pulmonary artery pressure. Attenuation of pulsus alternans has been rarely reported and may represent further deterioration of ventricular function.

Rapid identification of the course of anomalous coronary arteries in adults: the "dot and eye" method

It is often difficult to delineate the true course of anomalous coronary arteries by angiography because it only provides a 2-dimensional view of a complex 3-dimensional structure. The purpose of this study was to confirm morphologically the radiographic appearance of anomalous coronary arteries and to construct a protocol for rapid determination of their true course. Twenty-one adults who had anomalous origin of coronary arteries without other evidence of congenital heart disease were reviewed. Using an anatomically correct model of the heart, solder wire was placed in the pathologically described anomalous positions and radiographed. With this model the pathologically described courses could be easily recognized and separated radiographically. These courses were confirmed in the operating room in 2 patients and a rare anomaly of posterior origin of a coronary artery was also confirmed by autopsy.

Initial report of the National Registry of Elective Cardiopulmonary Bypass Supported Coronary Angioplasty

Relative contraindications to coronary angioplasty have been large amounts of jeopardized myocardium and poor left ventricular function. To prevent possible hemodynamic collapse after balloon occlusion or acute vessel closure in such high risk patients, a cardiopulmonary bypass system capable of providing up to 6 liters/min output was employed prophylactically. This technique, termed supported angioplasty, results in reductions of preload and afterload and allows prolonged balloon inflations in critical coronary vessels. A National Registry of 14 centers performing elective supported angioplasty was formed to collate the initial experience with high risk patients. Suggested indications were ejection fraction less than 25% or a target vessel supplying more than half the myocardium, or both. During 1988, the data from 105 patients (mean age 62 years) undergoing supported angioplasty were entered into the Registry. This group included 20 patients whose disease was deemed too severe to permit bypass surgery and 30 patients who had dilation of their only patent coronary vessel. Seventeen patients had stenosis of the left main coronary artery and 15 underwent dilation of that vessel. Chest pain and electrocardiographic changes occurred uncommonly despite prolonged balloon inflations. During the trial, there was a progressive change from cutdown insertion to percutaneous insertion of the circulatory support cannulas. The angioplasty success rate was 95% for the 105 patients, who underwent an average of 1.7 dilations per patient. Morbidity was frequent (41 patients), in most cases due to arterial, venous or nerve injury associated with cannula insertion or removal, or both.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic and echocardiographic assessment of the effects of diltiazem during transient occlusion of the left anterior descending coronary artery during percutaneous transluminal coronary angioplasty

The effects of diltiazem during transient myocardial ischemia were studied in 17 patients (age 58 +/- 11 years, 12 men, 5 women) undergoing 1-vessel left anterior descending percutaneous transluminal coronary angioplasty (PTCA). After hemodynamic, echocardiographic and electrocardiographic data were obtained during the control ischemic periods, diltiazem (10 mg intravenous bolus with 500 micrograms/min infusion) was given and 15 minutes later ischemia reinduced. Diltiazem reduced mean arterial pressure (113 +/- 16 to 95 +/- 15 mm Hg, p less than 0.05) and heart rate-pressure product (p less than 0.05) with no change in heart rate, pulmonary pressures or coronary (sinus, thermodilution technique) blood flow at rest. After diltiazem, times to ischemia-induced 1.0 mm ST-segment elevation (28 +/- 10 to 42 +/- 17 seconds, p less than 0.05) and new left ventricular wall motion abnormalities (by 2-dimensional echocardiography, 24 +/- 8 to 36 +/- 12 seconds, p less than 0.001) were prolonged without significant augmentation of great cardiac vein flow during coronary occlusion. Left ventricular (LV) ejection fraction decreased from 51 +/- 7 to 41 +/- 12% (p less than 0.05) during control ischemia, but declined less after diltiazem (54 +/- 12 to 47 +/- 14%, difference not significant; 47 +/- 14 vs 41 +/- 12%, p less than 0.01). Diltiazem can attenuate, but not abolish, some of the effects of myocardial ischemia on LV function during transient coronary artery occlusion. These data support the use of diltiazem as a beneficial adjunct that may be used acutely and safely during routine PTCA.

Improved method for transcatheter retrieval of intracoronary detached angioplasty guidewire segments

A transcatheter technique using a probing catheter and 0.014 wire to form a loop snare was used percutaneously to safely retrieve segments of retained guidewire fragments in mid- and distal coronary arteries in three patients.

Extracorporeal membrane oxygenation for percutaneous coronary angioplasty in high risk patients

Improvements in percutaneous coronary angioplasty (PTCA) have broadened the scope of this therapy to higher risk patients. The authors used an extracorporeal membrane oxygenator (ECMO) system during seven PTCA procedures to provide rapid, safe, cardiopulmonary support for high-risk patients. Six patients underwent femoral cutdown and placement of arteriovenous cannulae before PTCA; one patient was cannulated percutaneously. In two patients, no ECMO support was used, whereas two of the remaining five patients were maintained on low flow (1.5 L/min) during the procedure and three patients were maintained with higher flows (average 3.0 L/min). All patients were removed from cardiopulmonary support with satisfactory hemodynamics and maintained on i.v. heparin for 12-48 hours. In six patients groin hematomas developed, in four deep venous thrombosis developed, and in one patient arterial occlusion after percutaneous cannulation developed. One patient died of retroperitoneal hemorrhage unrelated to the ECMO cannulation site. Six patients survived. This system can be rapidly deployed while providing satisfactory cardiopulmonary support.

The effects of successful PTCA on left ventricular function: assessment by exercise echocardiography

To assess the usefulness of exercise echocardiography in the follow-up of patients after percutaneous transluminal coronary angioplasty (PTCA), we studied 56 patients at rest and immediately following exercise with two-dimensional echocardiography. Sixty-nine of 73 stress/echo studies (94%) were suitable for interpretation. Seventeen patients (group I) with significant coronary artery disease (CAD) were studied before and after PTCA. Sixteen patients with coronary disease not undergoing PTCA (group II) and 23 individuals without significant coronary disease (group III) served as age-matched controls. Left ventricular ejection fraction did not change significantly in group I patients prior to PTCA (56 +/- 7 versus 54 +/- 12, p = ns) or in group II patients (52 +/- 10 versus 56 +/- 15, p = ns), rest versus immediate after exercise measurements. Following angioplasty, left ventricular ejection fraction increased in group I patients from 55 +/- 7 to 65 +/- 8, p less than 0.001 from rest to exercise, and to a similar extent in group III individuals (55 +/- 6 to 66 +/- 8, p less than 0.001). Electrocardiographic (ECG) evidence of ischemia (greater than 1 mm ST segment depression) was found in 13 of 17 group I patients prior to PTCA and in 8 of 16 group II patients (CAD). None of the 25 normal patients and four of the group I patients following PTCA had abnormal ECG changes with exercise. New exercise-induced echocardiographic wall motion abnormalities were found in 12 of 17 group I patients prior to PTCA and in none of the group I patients following PTCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of pharmacologic coronary hyperemia on echocardiographic left ventricular function in patients with single vessel coronary artery disease

To assess whether pharmacologic coronary vasodilation could provoke new left ventricular wall motion abnormalities in patients with single vessel coronary artery disease, systemic hemodynamics, coronary blood flow velocity and left ventricular wall motion were measured by two-dimensional echocardiography during administration of 10 mg of intracoronary papaverine in 14 patients before and again immediately after left coronary angioplasty (group 1). As a comparison with an intravenous method, left ventricular wall motion was analyzed after 0.56 mg/kg body weight of intravenous dipyridamole in a separate group of 13 patients with single vessel coronary disease (group 2). Heart rate-blood pressure product increased 3% to 6% in papaverine-treated patients and 14 +/- 11% (p = NS) in dipyridamole-treated patients. No angiographic collateral vessels were present in either group. Although intracoronary mean flow velocity measured in the 14 group 1 patients and in 5 normal control subjects during papaverine treatment increased from 125% to 400% of basal flow velocity, papaverine induced new left ventricular wall motion abnormalities in only 5 of the 14 patients before coronary angioplasty. In three of five patients, left ventricular wall motion abnormalities persisted after successful coronary angioplasty. Four of the 14 patients demonstrated augmentation of left ventricular wall motion with papaverine. After intravenous dipyridamole, only 3 of the 13 group 2 patients developed new left ventricular regional asynergy. These data suggest that selective (papaverine) and, most likely, global (dipyridamole) augmentation of coronary flow alone does not reliably identify potential ischemic left ventricular regions affected by critical single vessel coronary artery disease.

Impaired coronary vasodilator reserve in the immediate postcoronary angioplasty period: analysis of coronary artery flow velocity indexes and regional cardiac venous efflux

The ratio of peak hyperemic/basal mean coronary flow velocity, an index of coronary vasodilator reserve, immediately after coronary angioplasty normalizes in less than 50% of patients. To evaluate other indexes of coronary vasodilator capacity, both intracoronary arterial velocity and cardiac venous efflux were measured at rest and during vasodilator-induced coronary hyperemia (intracoronary nitroglycerin and papaverine) before and after angioplasty in 27 patients; 17 patients had measurements of intracoronary velocity alone and 10 had thermodilution measurements of great cardiac vein flow. Coronary flow velocity responses were also measured in 6 angiographically normal segments in patients undergoing angioplasty and in 10 normal left coronary artery segments in patients with normal coronary arteries or isolated right coronary artery disease. Despite significant angiographic (72 +/- 12 to 23 +/- 11% diameter narrowing) and hemodynamic (49 +/- 12 to 19 +/- 12 mm Hg aortocoronary gradient) improvement, coronary vasodilator reserve ratios for both arterial velocity and venous flow after angioplasty were only minimally affected. Angioplasty did not significantly increase rest coronary vein flow or artery flow velocities, but did result in significantly higher papaverine responses after angioplasty. Mean and phasic coronary velocity, diastolic coronary flow velocity integral and measured great cardiac vein flow ratios were significantly lower when compared with those in 16 angiographically normal coronary artery segments. These data indicate that maximal hyperemic coronary flow velocity is increased after angioplasty, but the reserve ratios, calculated by any of several flow velocity indexes, remain minimally improved. Angiographic correlations (percent coronary diameter, absolute diameter or cross-sectional area) with variables of coronary blood flow or velocity suggest that no single variable is useful in assessing angioplasty results. However, postangioplasty arterial mean velocity and diastolic flow velocity integral are nearly normalized in most patients, whereas relative changes remain attenuated. These findings are important in studies assessing coronary vasomotor responses in patients with atherosclerotic coronary disease, especially after angioplasty.

Acute coronary occlusion occurring after successful percutaneous transluminal coronary angioplasty: temporal relationship to discontinuation of anticoagulation

The incidence and prognosis of acute coronary reocclusion occurring after patients had left the catheterization laboratory following a successful percutaneous transluminal coronary angioplasty (PTCA) procedure and the temporal relation of this event to the discontinuation of systemic heparin administration were analyzed in a series of 1238 consecutive patients. Acute reocclusion, 1 to 96 hours after successful PTCA, occurred in 22 of 1238 patients (1.8%). Patients undergoing PTCA in the setting of acute myocardial infarction were excluded. Out of 22 patients, 15 had a nonocclusive dissection and four had evidence of small intracoronary thrombus immediately post-PTCA, with no evidence of flow disturbance. Acute reocclusion occurred within 5 hours of heparin discontinuation in 12 patients or while they were receiving inadequate anticoagulation (four patients). In 16 of 22 (73%) patients, acute reocclusion was temporally related to a time of diminished anticoagulation. Redilation was attempted in 14 patients and was ultimately successful in five patients (36%). Ten patients required coronary artery bypass surgery and three patients died. Our findings suggest that acute reocclusion after an initially successful PTCA has a poor outcome and seems to be temporally related to the loss of effective anticoagulation in most of these patients. It is advisable to discontinue heparin infusion at a time when facilities for urgent revascularization are available.

Effects of nitroglycerin and nifedipine on coronary and systemic hemodynamics during transient coronary artery occlusion

Nitroglycerin (NTG) and nifedipine (NIF) have the potential to augment coronary blood flow in addition to reducing peripheral determinants of myocardial oxygen demand as a synergistic protective mechanism during ischemia. To examine these effects, systemic and coronary hemodynamic responses were measured continuously before and during brief periods of myocardial ischemia induced by left anterior descending coronary balloon occlusion in 26 patients undergoing angioplasty (PTCA). Data were compared for two matched occlusion periods, one control and one "drug" occlusion. In 17 patients (NTG group), 200 micrograms of intracoronary NTG was given immediately before coronary occlusion. In nine patients (NIF group), 10 mg of sublingual NIF was given 15 minutes before the "drug" occlusion. NTG significantly but transiently reduced mean arterial pressure (91 +/- 11 to 82 +/- 15 mm Hg, p less than 0.05) and augmented basal coronary blood flow (95 +/- 38 to 127 +/- 54 ml/min, p less than 0.05) but did not alter great vein blood flow (59 +/- 29 vs 61 +/- 29 ml/min) or coronary occlusion pressure (25 +/- 7 to 24 +/- 7 mm Hg) during ischemia. NIF significantly reduced systolic, diastolic, and mean arterial pressure (119 +/- 21 to 95 +/- 8 mm Hg, p less than 0.001) and heart rate-pressure product from control. NIF maintained basal great vein blood flow (125 +/- 41 to 106 +/- 57 ml/min) during reduced myocardial oxygen demand, but did not affect great vein blood flow (73 +/- 29 to 79 +/- 37 ml/min) or coronary occlusion pressures during ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous balloon valvuloplasty and coronary angioplasty for the treatment of calcific aortic stenosis and obstructive coronary artery disease in an elderly patient

An 81-year-old man with severe calcific aortic stenosis and coronary artery disease who refused surgical therapy was treated with sequential percutaneous balloon aortic valvuloplasty (PBAV) and percutaneous transluminal angioplasty. Before percutaneous balloon valvuloplasty, the mean aortic gradient was 76 mmHg, and the aortic valve area was .45 cm2. The aortic valve was dilated using 15-mm and 18-mm balloons. The mean gradient decreased to 40 mmHG, and the aortic valve area increased to .62 cm2. Percutaneous transluminal coronary angioplasty (PTCA) was performed 2 weeks later, and an 85% proximal left circumflex stenosis was successfully dilated to 20%. No complications were noted during either procedure. At 6-month follow-up, the patient had returned to normal activities and was asymptomatic. Thus, combined therapy with PBAV and PTCA is technically feasible in selected elderly patients with calcific aortic stenosis and anatomically suitable coronary artery disease. This nonsurgical therapeutic approach may be useful in the treatment of selected patients who refuse or who are deferred from cardiac surgery.

Percutaneous brachial catheterization: the hidden hazard of high brachial artery bifurcation

We describe a patient in whom a brachial arterial cutdown done at the same site for percutaneous transluminal angioplasty immediately after uncomplicated percutaneous brachial coronary arteriography revealed the percutaneous sheath in a deeper, smaller, and more lateral artery than the brachial artery, complicating placement of the guiding catheter. This case illustrates the potential hidden hazard of normal brachial artery bifurcation variants, which may be responsible for some of the potential complications encountered in percutaneous brachial artery catheterization techniques.

Acute myocardial infarction during percutaneous aortic balloon valvuloplasty

Balloon valvuloplasty has been shown to be a relatively safe and effective intervention in palliating the symptoms of severe calcific aortic stenosis in the elderly [1-7]. Although the mechanism of balloon valvuloplasty is plastic deformation and fracture of the calcified valve tissue [2], complications such as embolic events or acute myocardial infarction due to aortic balloon valvuloplasty are very rare. Previously published reports mentioned only one case of cerebral embolism [5] and two patients with late fatal myocardial infarction [4]. In this report we present an elderly patient with calcific aortic stenosis who developed an acute lateral myocardial infarction during percutaneous balloon aortic valvuloplasty.

Evaluation of left ventricular systolic and diastolic dysfunction during transient myocardial ischemia produced by angioplasty

Acute myocardial ischemia is known to cause impairment of both left ventricular systolic and diastolic function. To further investigate these changes as well as their relation to common clinical variables (electrocardiographic [ECG] changes and chest pain), 32 patients were evaluated with Doppler echocardiography during coronary angioplasty. Doppler indexes of left ventricular diastolic function included the ratios of peak early to late and peak early to mean diastolic velocities as well as the ratios of early to late and first third to total velocity integral (one-third filling fraction). All diastolic indexes showed significant impairment by 15 seconds after coronary occlusion (ratio peak early to late filling velocity: 1.11 versus 0.96, p less than 0.01; ratio peak early to mean filling velocity: 1.9 versus 1.7, p less than 0.01; ratio early to late velocity integral: 1.58 versus 1.25, p less than 0.01; one-third filling fraction: 41.2 versus 37.7, p less than 0.01). Left ventricular systolic function was evaluated during coronary occlusion both qualitatively, as assessed by the appearance of a new wall motion abnormality on two-dimensional echocardiography (mean 28.8 seconds), and quantitatively by measurement of systolic percent area change on the two-dimensional short-axis view as well as the Doppler echocardiographic stroke integral index. Systolic indexes did not show significant change until 30 seconds after balloon inflation (percent area change: 42.8 versus 29.2, p less than 0.01; stroke integral index: 11.04 versus 9.36, p less than 0.01). ECGs were performed at 15 second intervals.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative haemodynamic effects of intravenous flecainide in patients with and without heart failure and with and without beta-blocker therapy

The haemodynamic effects of flecainide were compared in three different subsets of patients with documented coronary disease. Ten patients (A) had no heart failure, 5 patients were on beta blockers (B) and 5 patients had overt heart failure (C). Flecainide was associated with negative inotropic effects that were relatively more pronounced in patients with left ventricular dysfunction: pulmonary wedge pressure increased by 27% in A, by 31% in B and by 42% in C; left ventricular stroke volume and stroke work decreased respectively by 10 and 12% in A, 21 and 19% in B, 26 and 28% in C. Ejection fraction decreased by 9% in A, 13% in B and 20% in C, in relation with an increase in end systolic volume (+9% in A, +10% in B and +5% in C). Absolute changes, however, were not significantly different from one group to another except for the increase of systemic vascular resistance which was more pronounced in C as compared with the other groups. The myocardial depression was also confirmed by the fall in dP/dt that was maximal at the end of injection; dP/dt remained depressed 15 min later despite some improvement. Flecainide thus exerts negative inotropic effects that are maximal at the end of infusion and may be of importance in patients with established left ventricular dysfunction.

Hemodynamic effects of intravenous diltiazem with impaired left ventricular function

The acute hemodynamic effects of intravenous diltiazem were studied in 8 patients with coronary artery disease, left ventricular (LV) failure (New York Heart Association functional class III), a rest ejection fraction (EF) less than 40% or a cardiac index less than 2.4 liters/min/m2. Hemodynamic measurements and LV angiograms were performed at rest before and after the administration of diltiazem, 0.5 mg/kg, administered at a speed of 5 mg/min. Diltiazem treatment induced a decrease in heart rate from 68 +/- 12 to 55 +/- 9 beats/min (p less than 0.001). Mean aortic pressure decreased from 94 +/- 14 to 81 +/- 15 mmHg (p less than 0.05). Thus, the pressure-rate product significantly decreased under the influence of the drug, from 8,791 +/- 2,465 to 6,342 +/- 1,808 beats mm Hg/min, (p less than 0.001). Diltiazem induced no significant change of LV end-diastolic pressure, pulmonary wedge pressure, cardiac index and LV stroke work index. Systemic vascular resistance decreased (p less than 0.01), whereas pulmonary vascular resistance showed no change. End-systolic volume diminished (p less than 0.02), which accounts for the increase of stroke volume and ejection fraction (p less than 0.001). Disorders of regional contractility were not aggravated by diltiazem, and even improved in individual cases. Thus, intravenous diltiazem may be used safely in patients with heart failure. However, in view of the marked bradycardic effects seen in some cases, heart rate should be carefully monitored.

Haemodynamic effects of intravenous diltiazem at rest and exercise in patients with coronary artery disease

The acute effects of intravenous diltiazem on exercise performance were studied in 10 patients with coronary artery disease. Haemodynamic measurements were made at rest and during exercise before and after 0.5 mg kg-1 of diltiazem. Diltiazem prolonged the duration of exercise (+2.85 min, P less than 0.001) and delayed the onset of ischaemic ST depression or angina in all patients. The highest tolerated heart rate and pressure rate product were increased in all but one patient after diltiazem. At rest diltiazem decreased mean arterial pressure (-10.8%, P less than 0.005), systemic vascular resistance (SVR) (-11.8%, P less than 0.05) and left ventricular stroke work index (SWI) (-14.1%, P less than 0.005). During exercise under diltiazem therapy, at the level achieved before the drug, the pulmonary capillary wedge pressure (-30%, P less than 0.005) and the SVR (-13.6%, P less than 0.02) were lowered, the SWI (+13%, P less than 0.01) was increased; at the end of exercise only the SVR (-14%, P less than 0.05) was reduced. Two patients experienced angina on lying down and one had orthostatic hypotension after exercise with diltiazem. This study indicates that intravenous diltiazem is a potentially useful agent for the treatment of angina by reducing myocardial oxygen demand at rest and by improving left ventricular performances on exercise.

Effects of dobutamine on left ventricular performance and myocardial metabolic demands in patients with ischemic heart disease

Sixteen patients with coronary artery disease undergoing cardiac catheterization were studied. Eleven had previous infarcts and the patients were divided into two groups: In group I were 7 patients with no left ventricular dysfunction, no increase in ventricular size, or symptoms of congestive failure; group II included 9 patients with ventricular dysfunction, increased ventricular size, and 7 of the 9 had congestive failure. Each patient underwent a continuous infusion of dobutamine from 2.5 to 10 micrograms/kg min-1 with dosage increments of 2.5 micrograms/kg at 15-minute intervals. Systemic and coronary hemodynamic measurements were obtained at the end of the 5 and 10 micrograms/kg min-1 infusion doses. Left ventricular performance improved (higher cardiac index, left ventricular stroke work index and mean systolic ejection rate, and lower left ventricular end-diastolic pressure), while heart rate, mean arterial pressure, and coronary sinus blood flow increased after dobutamine in the 16 patients. While patients in both groups had a rise in cardiac index, a reduction in left ventricular end-diastolic pressure, an unchanged mean arterial pressure and a rise in coronary blood flow, only patients in group I had a significant increase in heart rate, and only patients in group II had significant increases in left ventricular stroke work index and mean systolic ejection rate, and a significant reduction in systemic vascular resistance. Left ventricular oxygen consumption did not increase significantly in either group. However, 5 patients showed a decreased myocardial lactate extraction after 10 micrograms/kg min-1 of intravenous dobutamine, 3 from group I and 2 from group II.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic effects of a new antiarrhythmic agent, flecainide (R-818), in coronary heart disease

The hemodynamic effects of flecainide acetate, a new class I antiarrhythmic agent, were studied in 10 patients with coronary heart disease. The drug was injected intravenously at a dose of 2 mg/kg over 30 minutes. The mean drug plasma level achieved was 394 ng/ml (range 329 to 470). The heart rate did not change, but a significant increase (p less than 0.001) in P-R (+17%), QRS (+15%), and Q-T (+7%) duration occurred after drug administration. Negative inotropic effects also were observed and consisted of an increase (p less than 0.01) in pulmonary wedge pressure (+27%) and a decrease (p less than 0.01) in stroke index (-10%), left ventricular stroke work index (-12%), and left ventricular ejection rate (-11%). No significant change in mean aortic pressure or systemic and pulmonary vascular resistance occurred. Left ventriculography performed after drug infusion revealed a significant increase (p less than 0.01) in systolic volume (+9%) and a decrease in ejection fraction (-9%) and mean velocity of circumferential fiber shortening (Vcf) (-13%). A progressive and significant decrease of dP/dt was observed during drug infusion, but 15 minutes after the injection, dP/dt had returned to near basal values. Thus, flecainide acetate has slight, but significant negative inotropic effects, particularly conspicuous during drug infusion. The drug should be administered with caution in patients with poorly compensated heart.