SMART: The microstent's ability to limit restenosis trial.

In this randomized, prospective, multicenter trial (n = 661) of patients with de novo or restenotic coronary lesions, 330 patients received the MicroStent(R) II (MSII), and 331 received the Palmaz-Schatz (PS) stent. The short-term procedural success rates were 94.4% and 95.7%, respectively (P = 0.47). The 30-day cumulative incidence of major adverse events [death, myocardial infarction, CVA, target lesion revascularization (TLR)] was 6.4% for the MSII and 4.5% for the PS stent (P = 0.31). The in-stent binary restenosis rate at 6 months was 25.2% for the MSII and 22.1% for the PS stent (P = 0.636). Using Kaplan-Meier estimates, the incidence of clinically driven TLR was 8.9% for the MSII and 9.2% for the PS stent at 180 days; at 270 days, it was 12.8% and 12.1%, respectively (P = 0.83). MSII and the PS stents were comparable with respect to short-term procedural success, complications, and late clinical and angiographic restenosis.

Effect of primary balloon expandable renal artery stents on long-term patency, renal function, and blood pressure in hypertensive and renal insufficient patients with renal artery stenosis.

Stents were deployed in 83 renal artery lesions of 63 subjects. All were hypertensive and 29 were renal insufficient (RI). Technical success was 99%. Long-term (11.3 +/- 3.8 months) patency was evaluated with ultrasound in 69 lesions (51 ostial). Technical success and long-term patency rates were not significantly different between ostial and non-ostial lesions. Ten lesions restenosed (14%). At most recent follow-up (10.2 +/- 4.5 months) hypertensive subjects were classified as cured (3.7%), improved (35.2%), unchanged (53.7%), or worse (7.4%). Systolic pressure was significantly improved throughout follow-up but diastolic pressure was only significantly lower at discharge. Based on serum creatinine, Rl subjects were classified as improved (36%), unchanged (46%), or worse (18%). Complications included transfusion (10), renal artery perforation (3), and renal failure (8). Eight transfused subjects also had retroperitoneal bleeds. Rl subjects were more likely to develop acute renal failure. Subjects who died (9) were more likely to have Rl at baseline and to suffer renal artery perforation during the procedure. Patient risk factors and procedural technique contributed to complications in this study, but for most patients stenting yielded excellent technical success and long-term patency for ostial and non-ostial lesions. The effect on blood pressure and renal function was favorable.

Multicenter trial of the wallstent in the iliac and femoral arteries.

PURPOSE: To report the results of the FDA phase II, multicenter trial of the Wallstent in the iliac and femoral arteries. PATIENTS AND METHODS: Two hundred twenty-five patients entered the trial. Stents were placed in the iliac system in 140 patients and in the femoral system in 90 (five patients required both iliac and femoral stents). Clinical patency was measured over 2 years by means of life-table analysis with use of clinical and hemodynamic data and the Rutherford scale. Angiographic patency was measured at 6 months. RESULTS: In the iliac system the primary clinical patency was 81% at 1 year and was 71% at 2 years. The secondary clinical patency was 91% and 86%, respectively. The 6-month angiographic patency was 93%. In the femoral system the primary clinical patency was 61% at 1 year and 49% at 2 years. The secondary patency was 84% and 72%, respectively. The 6-month angiographic patency was 80%. CONCLUSIONS: The results are similar to those with the Palmaz stent in the iliac system and with angioplasty alone in the iliac and femoral systems.

Coronary angioplasty for acute myocardial infarction in a hospital without cardiac surgery.

We evaluated, retrospectively, the hospital records of 100 consecutive patients with acute myocardial infarction who underwent emergency coronary angiography and percutaneous transluminal coronary angioplasty between January 1984 and August 1990. Intracoronary streptokinase (250,000 to 1 million units) was administered to 46 of these patients. Reperfusion was achieved in 82 patients, 8 of whom died in the hospital within 30 days. Angioplasty failed in 18 patients. Six were managed medically and survived, 7 survived emergency coronary bypass surgery at a nearby facility, and 5 died. The overall mortality rate was 13%. No facilities for open-heart surgery were available at our hospital; however, surgical back-up was available at another hospital, 0.5 miles away. No death was related to the transfer of a patient or to the unavailability of an in-house cardiac surgery facility. The American College of Cardiology/American Heart Association Task Force on Assessment of Diagnostic and Therapeutic Cardiovascular Procedures has written guidelines for cardiac surgical back-up for percutaneous transluminal coronary angioplasty. These guidelines strongly recommended that an experienced cardiovascular surgical team be available for emergency surgery in the institution as a back-up for all angioplasty procedures. Our study shows, however, that with careful case selection, emergency angioplasty for acute myocardial infarction can be performed safely with good results in a setting without on-site cardiac surgery facilities.

Benefits of combined balloon pumping and percutaneous cardiopulmonary bypass.

Sixteen patients (2 women, 14 men) aged 29 to 72 years with continued cardiogenic shock during intraaortic balloon pumping (IABP) had additional treatment with percutaneous cardiopulmonary bypass (PBY). Cause of cardiogenic shock was myocardial infarction in 7 (3 survived), failed percutaneous transluminal coronary angioplasty requiring emergency coronary artery bypass grafting in 5, postoperative aortic valve replacement in 1, postoperative emergency coronary artery bypass grafting in 1, after cardiac transplantation in 1, and bridging to transplantation in 1. Mean blood pressure with PBY and IABP combined was 75 mm Hg versus 60 mm Hg with IABP off. Percutaneous cardiopulmonary bypass flows ranged from 0.8 to 2.1 L/min with a mean flow of 1.3 L/min. Time on IABP ranged from 24 hours to 1 week. Time on IABP to PBY ranged from 1 to 20 hours, and time on PBY ranged from 65 minutes to 20 hours. Ten of 16 (63%) were successfully weaned, and 3 died after weaning. Seven of 16 (44%) survive. Combined IABP with PBY appears to be a better therapy than either one individually. Staging the therapy as the balloon first in and last out appears to be a good methodology.

Sheathless insertion of the percutaneous intraaortic balloon pump: an alternate method.

A technique is described that allows insertion of a standard percutaneous intraaortic balloon without use of the larger 12F sheath. Standard 9.5-cm. Percor balloons were inserted in a series of patients without using the provided sheath. Elimination of the sheath reduced the potential vascular complications related to the extra bulk placed in the femoral artery by the sheath. No serious complications were noted in more than 25 patients.

Takayasu's disease with axillary, right coronary artery, and right internal mammary stenosis treated with angioplasty.

A 47-year-old woman presented with progressive angina and failed medical therapy. After an unsuccessful attempt at angioplasty of a totally occluded right coronary artery, coronary artery bypass using the right internal mammary artery was performed. She presented 2 years later with stenosis in the mammary graft, right coronary artery, and axillary artery. These lesions were all treated with angioplasty.

Disrupted coronary artery caused by angioplasty: supportive and surgical considerations.

Of 2,859 patients having percutaneous transluminal coronary angioplasty, 201 (7%) underwent emergency coronary artery bypass grafting. Two categories of patients were reviewed. Group 1 consisted of 126 patients of 2,304 who had immediate coronary artery bypass grafting after failed elective percutaneous transluminal coronary angioplasty. Ninety-eight of these patients had angiographic evidence of occlusion of a coronary artery, and 28 had angiographic evidence of coronary artery dissection. Epicardial hemorrhage was observed at operation in 20% (25 patients). Three deaths (2.4%) occurred in group 1, and an average of 3.3 grafts was performed per patient. Group 2 comprised 75 of 555 patients who had unsuccessful attempted percutaneous transluminal coronary angioplasty during an evolving myocardial infarction and required immediate coronary artery bypass grafting. Angiography revealed coronary artery occlusion in 61 patients with dissection in 14. All group 2 patients had evidence of myocardial injury by electrocardiographic and enzymatic (myocardial-specific isoenzyme of creatine kinase) criteria. Three deaths (4%) occurred in this group, and there was an average of 3.4 grafts per patient. Percutaneous transluminal coronary angioplasty is routinely performed without surgical consultation, although an operating room and team are usually available. Supportive techniques include the intraaortic balloon pump and percutaneous cardiopulmonary bypass. In those patients with coronary artery dissection, care must be taken to reestablish the true lumen of the coronary artery. Hemopericardium should be surgically explored and broken guidewires or other foreign bodies or debris removed. From 1979 through 1986, the number of patients requiring emergency coronary artery bypass grafting after percutaneous transluminal coronary angioplasty steadily declined to less than 5%.

Percutaneous cardiopulmonary bypass: application and indication for use.

Percutaneous cardiopulmonary bypass (CPB) was used in 22 patients: 7 patients with cardiac arrest due to acute myocardial infarction; 4 patients in cardiac arrest because of failed angioplasty; 1 patient for high-risk elective angioplasty; 1 patient with massive pulmonary emboli; 2 patients with hypothermia; 2 pediatric patients (1 with sepsis and 1 in combination with extracorporeal membrane oxygenator support); 1 patient with refractory arrhythmia; and 4 patients with trauma. Percutaneous CPB involves a modified Seldinger technique that is easily applied. All patients except those with massive trauma were resuscitated with the use of percutaneous CPB. One patient requiring a very difficult proposed angioplasty received percutaneous CPB support while triple-vessel angioplasty was performed. Percutaneous CPB appears to be beneficial in resuscitating patients with refractory cardiac arrest or other forms of circulatory collapse except trauma. Limited use for brief periods in high-risk patients having elective angioplasty might be applicable.

Internal mammary artery versus saphenous vein graft to the left anterior descending coronary artery: prospective randomized study with 10-year follow-up.

In 1975, 80 patients undergoing revascularization were prospectively randomized to receive either a greater saphenous vein (SV) graft (41 patients, Group 1) or a left internal mammary artery (LIMA) graft (39 patients, Group 2) to the left anterior descending coronary artery (LAD). All patients were completely revascularized. The average number of grafts per patient in both groups was 3.2. Patients were followed 10 years; follow-up was 97.5% complete. Group 1 and Group 2 were compared in regard to mortality, treadmill response, myocardial infarction, reoperation, percutaneous transluminal coronary angioplasty, and return to work. Mortality in Group 1 was 17.9% versus 7.7% in Group 2 (p less than 0.05). Treadmill studies were positive in 17 Group 1 patients and 7 Group 2 patients (p less than 0.05). Myocardial infarctions occurred in 8 patients in Group 1 versus 3 in Group 2. The number of reoperations was 2 in Group 1 versus 1 in Group 2. Percutaneous transluminal coronary angioplasty was performed in 3 patients in Group 1 and 2 in Group 2. Repeat studies revealed 76.3% patency of the SV graft to the LAD (Group 1) and 94.6% patency of the LIMA graft to the LAD (Group 2). Cardiac-related mortality in Group 1 was 12.8% at 10 years (5 patients) versus 7.7% in Group 2 (3 patients). Based on this study, the IMA is a superior conduit for bypass to the LAD.

Intravenous balloon pumping for acute right ventricular failure.

A patient with acute right ventricular failure and severe hemodynamic instability following coronary artery revascularization was treated with intra-aortic and intravenous balloon pumping. The intravenous balloon was timed to inflate during diastole and deflate during systole as did the intra-aortic balloon; in fact, the two were connected to the same system through a Y-connector. The intravenous balloon acted as an artificial atrium, which allowed approximately 20% improvement in the cardiac output when this intravenous balloon was functioning. Hemodynamic stability was achieved with this system. Intravenous balloon pumping should be considered for patients with unstable hemodynamics secondary to acute right ventricular failure.

Coronary artery spasm following coronary artery revascularization.

Coronary artery spasm is a well-documented phenomenon in patients undergoing medial treatment. We describe coronary artery spasm occurring in the immediate postoperative period following coronary artery bypass operation. The spasm occurred in a vessel that was not operated on and that had no apparent lesion. The diagnosis of spasm was made by coronary angiography immediately after operation. Complications associated with this spasm are discussed. Emphasis is placed on early postoperative angiography for patients whose condition is inexplicably unstable after operation.

A new left ventricular assist device: clinical experience in two patients.

A permanent parallel aortic pump (PAP), essentially a permanent intra-aortic balloon pump or modified dynamic aortic patch, has been designed to support failing left ventricles The PAP is a counterpulsation system in which an external energy source delivers a pulsatile wave into the central circulation during cardiac diastole and relaxes during cardiac systole. Clinical improvement occurred in two patients after PAP implantation. The initial regimen of continuous pumping evolved to intermittent left ventricular assistance, and the patients were able to be periodically disconnected from the pump and ambulated. The patients expired 39 and 34 days after implantation due to gastrointestinal bleeding and complications of chronic emphysema and tracheostomy. Autopsy revealed that surgery for both devices had entirely healed.