Hooshang Bolooki

Clinical impact of drug-eluting stents in changing referral practices for coronary surgical revascularization in a tertiary care center

BACKGROUND The long-term benefits of angioplasty are limited by the occurrence of restenosis. Drug-eluting stents with a projected restenosis rate of close to 0% are soon to become available. The short- and long-term consequences of this advance to the cardiac surgical volume remain unclear. METHODS A total of 196 consecutive coronary angiograms and medical records of patients referred for coronary bypass surgery were reviewed. Considering the hypothetical premise of having drug-eluting stents with a near zero restenosis rate, we reviewed each case to determine if surgical revascularization was still the preferred option for revascularization. RESULTS The mean age was 60 (+/-10.6) years. Seventy-two percent of patients were male. Considering the availability of drug-eluting stents 154 (79%) would still have been sent to surgery, representing a 21% decrease in the number of surgical revascularizations. Angiographic characteristics predicting coronary bypass revascularization were the presence of chronic total occlusion (odds ratio [OR]: 9.1; confidence interval [CI]: 2.1 to 39), left main coronary artery stenosis (OR: 9.6; CI: 1.27 to 73), and need for valvular surgery (OR: 7.38; CI: 1.3 to 157). The most common predictors of a change in clinical management from surgical to percutaneous revascularization if drug-eluting stents were available were diffuse coronary narrowing (OR: 15.78), restenotic lesions (OR: 27.86), and small coronary arteries (OR: 26). CONCLUSIONS Drug-eluting stents may have a significant impact on cardiac surgery volume (approximately a 21% decrease in our center). It may also direct patients with small vessels, diffuse narrowing, or restenotic lesions and diabetic patients to percutaneous therapy.

Myocardial revascularization after acute infarction

The purpose of this study was (1) to establish the maximal interval between the onset of ischemia and reperfusion that would permit a decrease in the size of infarction, and (2) to evaluate the relation between changes in infarct size and preservation of cardiac function. Studies were carried out in 19 dogs of which 13 had temporary (1 to 3 hours) occlusion of the left anterior descending coronary artery. The hospital course of 15 patients of whom 13 underwent myocardial revascularization within 8 hours of acute infarction was also reviewed. In dogs, the eventual pathologic infarct size was significantly reduced if reperfusion was performed within 2 hours of ischemia. After 2 hours of ischemia, the revascularized segment remained dyskinetic on angiographic assessment and cardiac function was depressed. After 3 hours of ischemia, in spite of a patent coronary artery, the extent of infarct and dykinesia was greater than during ligation of the left anterior descending coronary artery. In patients, small infarcts developed with revascularization performed more than 4 hours after infarction but with revascularization of the left anterior descending coronary artery the size of the dyskinetic area (as assessed with angiography) was similar to that in patients with a closed graft to the left anterior descending coronary artery but with a patent graft to its diagonal branch. In all patients after revascularization the extent of the left ventricular dyskinetic area was smaller and cardiac function was significantly better than in patient who did not receive revascularization for complete occlusion of the left anterior descending coronary artery. In spite of successful revascularization, electrocardiographic evidence of transmural infarction persisted postoperatively. It is concluded that reperfusion of an area of myocardium that has been ischemic for less than 2 hours in dogs or less than 4 hours in man may lead to a significant reduction in the extent of infarction as well as improvement in cardiac function. However, the revascularized area remains angiographically dyskinetic and electrocardiographically abnormal.

Transvenous Caval Interruption with Umbrella Filter

Abstract For prevention of pulmonary embolism, transvenous interruption of the inferior vena cava by the umbrella filter was performed in 100 patients between July, 1968, and June, 1970. Filter dis...

Oral amiodarone reduces incidence of postoperative atrial fibrillation.

BACKGROUND Atrial fibrillation (AF) is a common occurrence after heart operations that use cardiopulmonary bypass. It can cause life-threatening complications as well as delay discharge and increase hospitalization costs. The purpose of this study was to evaluate the effect of orally administered low-dose amiodarone on the incidence of new onset postoperative AF. METHODS In this prospective study, 226 consecutive adult patients (group A) who had various heart operations utilizing cardiopulmonary bypass between April and November of 1998 at the University of Miami/Jackson Memorial Hospital, were given oral amiodarone (200 mg three times a day), starting immediately after arrival in the intensive care unit until the day of hospital discharge. The incidence of new AF in this group of patients was assessed and compared with a historical group of 239 patients (group B) who had had cardiac operations with cardiopulmonary bypass in the preceding 9 months at the same institution. RESULTS Preoperative patient characteristics and procedure types were similar in the two groups. Among the 226 patients in group A, 13 (5.7%) had history of AF. Of the remaining 213 patients, new-onset AF occurred postoperatively in 10 (4.7%). Among the 239 patients in group B, 16 (6.7%) had history of AF. Of the remaining 223 patients, 44 (19.7%) developed new-onset AF (p < 0.001). Group A patients had a shorter length of hospital stay than those in group B (6.5 versus 7.8 days) but had a similar incidence of complications other than AF (23 of 226 patients in group A versus 24 of 239 in group B). The drug was well tolerated. CONCLUSIONS Postoperative low-dose amiodarone given orally to patients who had cardiopulmonary bypass was well tolerated and appeared to reduce the incidence of new-onset AF and decrease the length of hospital stay.

Factors affecting late survival after surgical remodeling of left ventricular aneurysms

OBJECTIVES Surgical remodeling of the left ventricle has involved various techniques of volume reduction. This study evaluates factors that influence long-term survival results with 3 operative methods. METHODS From 1979 to 2000, 157 patients (134 men, mean age 61 years) underwent operations for class III or IV congestive heart failure, angina, ventricular tachyarrhythmia, and sudden death after anteroseptal myocardial infarction. The preoperative ejection fraction was 28% +/- 0.9% (mean +/- standard error), and the pulmonary artery occlusive pressure was 15 +/- 0.07 mm Hg. Cardiogenic shock was present in 26 patients (16%), and an intra-aortic balloon pump was used in 48 patients (30%). The type of procedure depended on the extent of endocardial disease and was aimed at maintaining the ellipsoid shape of the left ventricle cavity. In group I patients (n = 65), radical aneurysm resection and linear closure were performed. In group II patients (n = 70), septal dyskinesis was reinforced with a patch (septoplasty). In group III patients (n = 22), ventriculotomy closure was performed with an intracavitary oval patch. RESULTS Hospital mortality was 16% (25/157) and was similar among the groups. Actuarial survival up to 18 years was better with a preoperative ejection fraction of 26% or greater (P =.004) and a pulmonary artery occlusive pressure of 17 mm Hg or less (P =.05). Survival was worse in patients who had intra-aortic balloon pump support (P =.03). Five-year survival for all patients in group III was higher than for patients in group II (67% vs 47%, P =.04). CONCLUSIONS Factors that improved long-term survival after left ventricular surgical remodeling were intraventricular patch repair, preoperative ejection fraction of 26% or greater, and pulmonary artery occlusive pressure of 17 mm Hg or less without the need for balloon pump assist.

Late complications of plombage

Plombage was used commonly in the management of tuberculosis before the early 1950s. From 1977 through 1990, 4 patients were seen with complications of plombage performed decades previously. Lucite spheres were used in 3 patients and paraffin in 1. One patient had bilateral apical plombage. In all cases, complications were related to infection or migration of the foreign material. Two patients had extrusion of foreign material or fluid into the chest wall. One patient had hemoptysis and infection due to erosion of a Lucite sphere into the lung. Another had intestinal obstruction subsequent to erosion into the esophagus. The patient with bilateral plombage had development of asynchronous complications on both sides. Treatment consisted of removal of the foreign material and individualized management of the remaining space. There were no operative deaths and the outcome was good in all cases.

Comparison of Long-Term Results of Carpentier-Edwards and Hancock Bioprosthetic Valves

The long-term survival following valve replacement with Carpentier-Edwards or Hancock bioprostheses was compared between the two valve models and between the two groups totaling 407 patients who were discharged after valve replacement beginning in 1974. The two groups of patients were treated in a nonrandomized fashion. The actuarial survival for 299 patients with Carpentier-Edwards valves was 94 +/- 1.5% (+/- standard error) and 93 +/- 1.7% after 5 and 8 years of follow-up, respectively. Comparable figures for 108 patients undergoing valve replacement with Hancock valves were 89 +/- 3.0% and 83 +/- 3.7%, respectively (p = not significant [NS]). The probability of freedom from death and valve removal after 5 and 8 years of follow-up was 91 +/- 1.8% and 79 +/- 4.6%, respectively, with the Carpentier-Edwards valve and 84 +/- 3.5% and 75 +/- 4.3%, respectively, with the Hancock valve (p = NS). An accelerated rate of attrition for both valves was observed in the mitral position. There were no significant differences in actuarial survival between the two valves in the mitral or the aortic position or in the incidence of major valve-related complications.

Failure of Hancock Xenograft Valve: Importance of Valve Position (4- to 9-Year Follow-up)

To evaluate long-term durability of Hancock valves, we reviewed our results in 107 hospital survivors (120 valves) who were operated on during 1974 through mid-1979. Mitral valve replacement was done in 63 patients, aortic valve replacement in 20, and mitral valve replacement combined with other procedures in 24. The 7-year survival was 84 +/- 4% (standard error of the mean) for 91 patients and 97 valves. During a follow-up of 590 patient-years, 15 (12 mitral and 3 aortic) of 120 valves at risk (87 mitral, 32 aortic, 1 tricuspid) were removed from 14 patients. Six valves (3 mitral and 3 aortic) were removed because of bacterial endocarditis. One mitral valve was removed because of thromboembolism. Eight mitral valves were removed because of valve structural failure, which occurred at a mean follow-up of 42 months. These valves showed extensive calcification, leaflet perforation, or cusp tear. Structural failure was unrelated to valve size, year of implantation, or valve shelf-life. Structural failure was not seen after aortic valve replacement. Results show that structural failure of the Hancock xenograft valve in the mitral position is related primarily to valve position. After aortic valve replacement, valve failure is predominantly due to endocarditis. Although medium-term (mean, 6-year) durability of this xenograft valve compares satisfactorily with prosthetic valves, its high failure rate in the mitral position indicates the necessity for improvement in valve mounting, design, and preservation.

Sinus of valsalva aneurysm presenting as myocardial infarction during dobutamine stress test

We report a patient with an undiagnosed left sinus of Valsalva aneurysm who, during a dobutamine stress test, had myocardial injury and subsequent infarction. Cardiac catheterization revealed an expanding sinus of valsalva aneurysm compressing the circumflex coronary artery. The clinical manifestations of sinus of Valsalva aneurysm are discussed. This report heightens awareness of the possible effects of the pharmacologic stress test.

Sequential internal mammary artery grafts for coronary artery bypass

From 1985 to 1990, 145 patients underwent isolated coronary artery bypass with one (n = 128) or both (n = 17) internal mammary arteries (IMAs) used as sequential bypass grafts. All but 2 patients had angina pectoris preoperatively. A total of 162 sequential IMA grafts were constructed bypassing two (n = 152) or three (n = 10) coronary artery sites as in situ (n = 132) or free (n = 30) grafts. In 12 patients, one IMA was used as a nonsequential graft. Thirty-day mortality was 2.8% (n = 4 patients). Perioperative myocardial infarction occurred in 1 patient (0.7%). Only two sequential IMA grafts failed. Both were used to bypass coronary arteries 1.00 mm in diameter. Mean follow-up was 31 months (range, 6 months to 4.2 years). There were three late deaths. Of 136 survivors followed-up, 121 (89%) were free of angina. Postoperative rotational thallium 201 tomography was done in 73 patients. Myocardial ischemia was detected in 11 diabetic patients (15.1%), but corresponded to a sequential IMA graft in 4 (5.5%) and to nonsequential and venous grafts in 10 patients (13.7%). Coronary revascularization with sequential IMA grafts was safe and effective.