A prospective, randomized evaluation of prophylactic intraaortic balloon counterpulsation in high risk patients with acute myocardial infarction treated with primary angioplasty. Second Primary Angioplasty in Myocardial Infarction (PAMI-II) Trial Investigators.

OBJECTIVES: A large, international, multicenter, prospective, randomized trial was performed to determine the role of prophylactic intraaortic balloon pump (IABP) counterpulsation after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI). BACKGROUND: Previous studies have suggested that routine IABP use after primary PTCA reduces infarct-related artery reocclusion, augments myocardial recovery and improves clinical outcomes. METHODS: Cardiac catheterization was performed in 1,100 patients within 12 h of onset of AMI at 34 clinical centers. Clinical and angiographic variables were used to stratify patients undergoing primary PTCA into high and low risk groups. High risk patients were then randomized to 36 to 48 h of IABP (n = 211) or traditional care (n = 226). The study had 80% power to detect a reduction in the primary end point from 30% to 20%. RESULTS: There was no significant difference in the predefined primary combined end point of death, reinfarction, infarct-related artery reocclusion, stroke or new-onset heart failure or sustained hypotension in patients treated with an IABP versus those treated conservatively (28.9% vs. 29.2%, p = 0.95). The IABP strategy conferred modest benefits in reduction of recurrent ischemia (13.3% vs. 19.6%, p = 0.08) and subsequent unscheduled repeat catheterization (7.6% vs. 13.3%, p = 0.05) but did not reduce the rate of infarct-related artery reocclusion (6.7% vs. 5.5%, p = 0.64), reinfarction (6.2% vs. 8.0%, p = 0.46) or mortality (4.3% vs. 3.1%) and was associated with a higher incidence of stroke (2.4% vs. 0%, p = 0.03). IABP use did not result in enhanced myocardial recovery as assessed by paired admission to predischarge and 6-week rest and exercise left ventricular ejection fraction. CONCLUSIONS: In contrast to previous studies, a prophylactic IABP strategy after primary PTCA in hemodynamically stable high risk patients with AMI does not decrease the rates of infarct-related artery reocclusion or reinfarction, promote myocardial recovery or improve overall clinical outcome.

Safety and cost-effectiveness of early discharge after primary angioplasty in low risk patients with acute myocardial infarction. PAMI-II Investigators. Primary Angioplasty in Myocardial Infarction.

OBJECTIVES: The second Primary Angioplasty in Myocardial Infarction (PAMI-II) study evaluated the hypothesis that primary percutaneous transluminal coronary angioplasty (PTCA), with subsequent discharge from the hospital 3 days later, is safe and cost-effective in low risk patients. BACKGROUND: In low risk patients with myocardial infarction (MI), few data exist regarding the need for intensive care and noninvasive testing or the appropriate length of hospital stay. METHODS: Patients with acute MI underwent emergency catheterization with primary PTCA when appropriate. Low risk patients (age <70 years, left ventricular ejection fraction >45%, one- or two-vessel disease, successful PTCA, no persistent arrhythmias) were randomized to receive accelerated care (admission to a nonintensive care unit and day 3 hospital discharge without noninvasive testing [n = 237] or traditional care [n = 234]). RESULTS: Patients who received accelerated care had similar in-hospital outcomes but were discharged 3 days earlier (4.2+/-2.3 vs. 7.1+/-4.7 days, p = 0.0001) and had lower hospital costs ($9,658+/-5,287 vs. $11,604+/-6,125 p = 0.002) than the patients who received traditional care. At 6 months, accelerated and traditional care groups had a similar rate of mortality (0.8% vs. 0.4%, p = 1.00), unstable ischemia (10.1% vs. 12.0%, p = 0.52), reinfarction (0.8% vs. 0.4%, p = 1.00), stroke (0.4% vs. 2.6%, p = 0.07), congestive heart failure (4.6% vs. 4.3%, p = 0.85) or their combined occurrence (15.2% vs. 17.5%, p = 0.49). The study was designed to detect a 10% difference in event rates; at 6 months, only a 2.3% difference was measured between groups, indicating an actual power of 0.19. CONCLUSIONS: Early identification of low risk patients with MI allowed safe omission of the intensive care phase and noninvasive testing, and a day 3 hospital discharge strategy, resulting in substantial cost savings.

Coronary reperfusion and Bezold-Jarisch reflex (bradycardia and hypotension).

This study reports the occurrence of bradycardia and hypotension (Bezold-Jarisch reflex) induced by myocardial reperfusion. Among 92 patients undergoing interventional catheterization for intracoronary thrombolysis in an early phase of acute myocardial infarction, left anterior descending, right coronary, and left circumflex (LC) arteries were identified as the "infarct vessel" in 44, 41, and 7 cases, respectively. The Bezold-Jarisch reflex occurred in 15 of 23 patients (65%) after right coronary recanalization and in 1 of 34 patients after left anterior descending recanalization. The reflex also was observed in 4 (22%) of 18 patients with nonoccluded or nonrecanalized right coronary arteries. The average time from onset of symptoms to right recanalization was significantly shorter (p less than 0.01) among patients in whom the reflex did not develop. Atropine, postural changes, or temporary pacing, or all 3, were generally sufficient to control symptoms. The findings of this study are substantially parallel to those reported by others and confirm that reperfusion of the inferoposterior myocardium is capable of stimulating a cardioinhibitory reflex. Follow-up data available in 15 patients with occluded and recanalized right coronary arteries indicate that the occurrence of the Bezold-Jarisch reflex after reperfusion is not a reliable predictor of myocardial salvage.

Successful early streptokinase thrombolysis of aortocoronary vein grafts.

Two patients recently underwent successful early thrombolytic recanalization of thrombosed saphenous vein coronary bypass grafts. This treatment strategy must be weighed against the potential risk of bleeding.

A systemic hemodynamic evaluation of indapamide.

The hemodynamic effects of indapamide were evaluated in an open clinical trial of nine patients with mild to moderate hypertension. Hemodynamic and echocardiographic measurements were made before and after six weeks of treatment with single daily doses of 2.5 mg of indapamide. Indapamide significantly reduced the mean standing systolic blood pressure (P less than 0.025), the mean standing diastolic blood pressure (P less than 0.01), the mean arterial blood pressure (P less than 0.001), and the mean total peripheral vascular resistance (P less than 0.01). Cardiac output increased 12% (P less than 0.05) during treatment. The heart rate, left ventricular end-diastolic and end-systolic volumes, systolic volume, and ejection fraction were not markedly altered after treatment with indapamide, although the systolic wall stress index fell slightly. Six weeks of indapamide administration was well tolerated with no notable adverse effects of the drug. The results suggest that indapamide reduces arterial blood pressure in hypertensive patients by decreasing total peripheral resistance.

Effect of lipid-lowering therapy on the progression of coronary atherosclerosis assessed by scheduled repetitive coronary arteriography.

We studied 42 subjects, each of whom demonstrated significant (greater than or equal to 50%) narrowing of a non-grafted coronary artery and a baseline cholesterol level greater than 250 mg%. All patients underwent repeat scheduled coronary arteriography after 2 years on the study. Twenty-five colestipol responders (cholesterol levels reduced at least 15% within 1 month of therapy) were compared to 17 non-responders who were given 23 months of placebo after a 1 month exposure to colestipol. Baseline risk factors and demographic characteristics were similar for the two groups. In comparison to baseline arteriography, only 3 of the 25 drug-treated patients showed progression, while 8 of 17 placebo treated patients demonstrated progression (P = 0.011). Drug-treated patients demonstrated a 20% decrease in cholesterol levels, while placebo patients did not experience a significant reduction in cholesterol levels. Our study suggests that significant reduction in serum cholesterol levels is associated with a reduced likelihood of progression of coronary atherosclerotic lesions assessed by scheduled repetitive coronary arteriography in hyperlipidemic subjects demonstrating significant coronary artery narrowing on their initial arteriograms.

Adjunctive therapies in the cath lab. Use of combination glycoprotein IIb/IIIa inhibitor and direct thrombin inhibitor drugs to support percutaneous coronary stent placement in a patient with renal insufficiency and heparin-induced thrombocytopenia.

An 81-year-old woman with a history of prior coronary artery bypass surgery, heparin-induced thrombocytopenia with "white clot" syndrome, and renal insufficiency presented with unstable angina. She was referred for cardiac catheterization. Complex percutaneous revascularization of the native circumflex coronary artery was performed using stents. A combination of tirofiban and lepirudin was used with dosing adjusted for renal insufficiency. The hospital course was uncomplicated and the patient was discharged on the fourth hospital day. This is only the second report of the combination use of direct thrombin inhibitor and glycoprotein IIb/IIIa receptor inhibitor.

Enoxaparin and abciximab adjunctive pharmacotherapy during percutaneous coronary intervention.

Randomized controlled trials of patients with non-ST segment elevation acute coronary syndromes have established the superiority of enoxaparin (versus unfractionated heparin) for reducing adverse ischemic outcomes. Furthermore, adjunctive abciximab therapy during percutaneous coronary intervention (PCI) is associated with improved clinical outcomes. Since algorithms for integrating these pharmacotherapies have not been determined, patients undergoing elective PCI were enrolled into 2 distinct and separate studies conducted by the National Investigators Collaborating on Enoxaparin (NICE) study groups (NICE 1 and NICE 4 studies). Patients in NICE 1 were administered enoxaparin 1.0 mg/kg intravenously (without abciximab) and those enrolled in NICE 4 were administered a reduced dose (0.75 mg/kg) of enoxaparin in combination with standard-dose abciximab intravenously during PCI. Bleeding events and ischemic outcomes assessed in-hospital and at 30-days post-PCI were infrequent with either pharmacologic regimen. In the dose regimens studied, enoxaparin with or without abciximab appears to provide safe and effective anticoagulation during PCI. The combination of reduced-dose enoxaparin and abciximab was associated with a low incidence of adverse outcomes (bleeding or ischemic events). Additional studies may be required to establish the relative safety and efficacy of this new adjunctive pharmacologic strategy when compared with the combination of low-dose, weight-adjusted unfractionated heparin and abciximab.

The use of injectable nitroglycerin in the cardiac catheterization laboratory. Nitroglycerin in cardiac catheterization.

At our institution, injectable nitroglycerin (TNG) has been employed during cardiac catheterization since 1976. Initially, it was primarily used in patients undergoing a provocative test for coronary spasm with ergonovine maleate. After the initial favorable experience, the use of injectable TNG became routine.

Angioplasty of a large aortocoronary bypass graft utilizing a single oversized balloon catheter.

Angioplasty of large saphenous vein grafts may present problems because of unavailability of adequately sized balloon dilatation catheters. We report a case of successful PTCA of a left anterior descending graft by using a 5 mm balloon and a standard 8F guiding catheter.

Comparison of the acute hemodynamic effects of intravenous celiprolol and propranolol in patients with suspected coronary disease.

The acute hemodynamic effects of intravenously administered celiprolol and propranolol were compared in 18 patients, 12 with coronary obstruction in the presence or absence of reduced LV function and six with no significant cardiac disease. The study was performed using a single blind, randomized design with celiprolol (0.07 and 0.14 mg/kg) and propranolol (0.07 mg/kg) in six patients per treatment group. The hemodynamic parameters obtained via right and left heart catheterization were measured at baseline and at 5 and 10 min after drug infusion (1.0 mg/min). Propranolol produced a significant fall in left ventricular Vmax, left ventricular dP/dt and cardiac output. In contrast, celiprolol either caused no change or significantly increased these parameters. These results indicate that celiprolol has an acute hemodynamic profile which differs significantly from that of propranolol.

Extensive coronary dissection caused by balloon rupture at high pressure during stent deployment.

A patient with severe stenosis of the right coronary artery underwent successful stent placement. During high pressure postdilatation, the balloon ruptured, causing an extensive proximal dissection of the right coronary artery managed with the deployment of several additional stents. Strategies aimed at avoiding or minimizing the consequences of high pressure balloon rupture are discussed.

Transradial cardiac catheterization in patients with prior brachial artery cutdown.

The safety and efficacy of transradial cardiac catheterization in patients with prior ipsilateral brachial cutdown is not known. Using standard techniques we performed transradial catheterization in 278 consecutive patients, of which 63 had prior brachial cutdown. All patients had a strongly palpable radial pulse and a negative Allen's test. Although patients with prior cutdown were older and had a higher incidence of hypertension and prior coronary artery bypass surgery, there was no significant difference in success rates for transradial catheterization (93.6% vs. 95.3%; P = NS). There were no periprocedural complications. Brachial artery occlusion was responsible for only two unsuccessful catheterization attempts. We conclude that, with careful preprocedural screening, ipsilateral transradial cardiac catheterization can be successfully performed in a majority of patients with prior brachial cutdown.

An unusual complication during deployment of a Multi-Link stent.

The use of intracoronary stents has greatly impacted on the practice of interventional cardiology. Complications due to equipment failure during deployment of stents are rare but potentially serious. We report a case of a malfunctioning Multi-Link delivery system and the successful treatment of the resulting complications.

Safety and efficacy of repeat transradial access for cardiac catheterization procedures.

To determine the safety and efficacy of repeat transradial cardiac catheterization, 1,362 consecutive transradial procedures were examined. Repeat transradial procedures were identified (group I, n = 73) and compared with index procedures (group II, n = 1,289). Baseline patient characteristics, procedure success rates (100% vs. 97.9%; P = NS), complication rates (0% vs. 0.08%; P = NS), and procedure times (23.9 +/- 27.3 min vs. 18.2 +/- 14.7 min; P = NS) were similar between groups. This study suggests that repeat transradial catheterization procedures can be performed safely and successfully in appropriately selected patients.