Experience with the use of coronary autoperfusion catheter during complicated angioplasty.

Between February and July of 1989, 22 patients underwent the use of the Stack autoperfusion catheter following acute occlusion or obstructive dissection during coronary angioplasty; in 20 cases conventional balloon was used in an attempt to correct the angiographic appearance followed by the use of Stack catheter when results were sub-optimal. Only 1 patient (4.5%) required surgical revascularization. Although our study is not prospective or randomized, our observations suggest a significant impact in decreasing the need for emergency surgical revascularization after complicated coronary angioplasty with the use of this approach.

Myocardial protection during transient coronary artery occlusion in man: beneficial effects of regional beta-adrenergic blockade.

The goal of this study was to verify whether myocardial protection could be achieved via the intracoronary administration of propranolol in patients undergoing percutaneous transluminal coronary angioplasty (PTCA). Accordingly, 21 patients undergoing PTCA were randomly assigned to receive either intracoronary placebo (group A, n = 10) or intracoronary propranolol (group B, n = 11). Three balloon inflations (i.e., coronary artery occlusions) were performed in each patient. Inflations I and II (maximum duration 60 sec) served as control occlusions. Inflation III (maximum duration 120 sec) was performed either after intracoronary administration of saline (2 ml) or propranolol (1.1 +/- 0.2 mg). The following electrocardiographic index of myocardial ischemic injury were measured: (1) time to development of ST segment elevation equal to 0.1 mV and (2) magnitude of ST segment elevation after 60 sec of coronary artery occlusion. Both indexes did not differ significantly between the groups during inflations I and II. In group A the time to development of ST segment elevation of 0.1 mV remained unchanged between the second and third occlusions (25 +/- 5 and 26 +/- 4 sec during inflations II and III, respectively). In group B subselective injection of propranolol into the affected coronary artery significantly prolonged the time to ST segment elevation of 0.1 mV from 19 +/- 4 sec (inflation II) to 53 +/- 9 sec (inflation III; p less than .001). Administration of placebo did not change the magnitude of ST segment elevation 60 sec after coronary artery occlusion between the second and third occlusion in group A (0.16 +/- 0.02 and 0.18 +/- 0.03 mV, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Improved stability and visualization during coronary artery angioplasty using a double catheter technique.

Guiding catheters used in coronary angioplasty can make coronary angioplasty potentially hazardous when they become positionally unstable, induce myocardial ischemia, or impair angiographic visualization. In order to avoid this problem, a double catheter technique was employed in seven patients involving nine procedures consisting of a standard 8 or 9 French angioplasty guiding catheter and a standard 7 French angiographic catheter to prevent coronary flow reduction and to permit improved coronary artery visualization. In two of the procedures, the second diagnostic catheter also permitted the prevention of potential plaque disruption by the guide catheter in the proximal right coronary artery. The predilatation stenosis was 88 +/- 12%; the postdilatation stenosis was 28 +/- 9%. The use of the diagnostic catheter as a second catheter prevented damping and permitted the stable disengagement of the guiding catheter from the coronary artery. This technique is most useful in patients who have proximal right coronary artery stenoses because it provides optimal visualization of the segment undergoing dilatation, avoids the potential for ischemia in more distal stenoses, and thereby allows the procedure to be performed in a controlled, unhurried manner.

Myocardial protection via coronary sinus interventions: superior effects of arterialization compared with intermittent occlusion.

It has been reported that infarct size can be reduced by several interventions, by which arterial blood is delivered retrogradely to the ischemic myocardium through the cardiac veins or alternatively the cardiac venous system is intermittently occluded. Accordingly, we studied several modalities of myocardial protection that used the cardiac venous system and compared them by means of a quantitative technique for measuring infarct size. Thus 73 anesthetized dogs with coronary arterial occlusion were randomized into the following groups: group I (n = 9), 6 hr of occlusion without any intervention; group II (n = 11), venovenous shunt (60 ml/min) to the great cardiac vein; group III (n = 11), arteriovenous shunt to the anterior interventricular vein; group IV (n = 12), high flow arteriovenous shunt to the anterior interventricular vein (60 ml/min); group V (n = 11), arteriovenous shunt to the great cardiac vein (60 ml/min); group VI (n = 10), arteriovenous shunt to the great cardiac vein (60 ml/min) combined with diastolic occlusion of the great cardiac vein; group VII (n = 9), intermittent pressure-controlled occlusion of the great cardiac vein without arterialization. The arteriovenous shunt (groups III to VI) or venovenous shunt (group II) was done by selective catheterization of the anterior interventricular vein or the great cardiac vein, advancing a catheter from the jugular vein through the right atrium and coronary sinus under fluoroscopic control. This catheter was then connected to a cannula located either in the carotid artery (groups III to VI) or in the right atrium (group II). One minute after occlusion, 99mTc-labeled albumin microspheres (8 mCi) were injected into the left atrium for the subsequent assessment of the hypoperfused zone, which is the area at risk for infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Unstable angina and evolving myocardial infarction following coronary bypass surgery: pathogenesis and treatment with interventional catheterization.

Effective therapy for patients with unstable angina or evolving myocardial infarction following coronary bypass surgery requires accurate delineation of the pathoanatomy and prompt intervention. We therefore performed cardiac catheterization in 10 consecutive patients: four with acute myocardial infarction and six with refractory unstable angina (NYHA class IV). All patients with acute myocardial infarction were found to have completely thrombosed vein grafts supplying totally occluded native coronary arteries. In three patients with evolving myocardial infarction occurring within 4 weeks of coronary bypass surgery, graft thrombosis was caused by venous valves in two patients and a suboptimal anastomosis in a third. The fourth patient sustained a myocardial infarction 7 years after coronary bypass surgery with atherosclerotic plaque rupture causing vein graft thrombosis. Therapy with intragraft streptokinase resulted in complete clearing of thrombus, pain relief, and control of injury current in all four patients. Rest angina with concomitant ST and T wave changes occurred in six patients. In two patients symptoms occurred early (within 6 months), whereas angina developed 4 to 10 years after coronary bypass graft surgery in four patients. In the two patients with early recurrence of symptoms suboptimal anastomosis was found in one, while the other patient had a venous valve in the vein graft in conjunction with a stenosis in the native coronary artery. In three of four patients with late recurrence of angina, symptoms developed as a result of atherosclerotic stenosis in their vein grafts; in the fourth patient an occluded graft was found to supply a stenosed native coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)