Search

This paper describes 3 patients who developed late severe stenosis in fresh antibiotics sterilised homograft valves. Two were in the aortic position and one in the mitral. All 3 patients underwent successful reoperation. This complication has not been previously reported in valves prepared by this method.

Between February 1984 and May 1988, 55 patients underwent orthotopic cardiac transplantation at the Brigham and Women's Hospital, Boston, Mass. Basic immunosuppression was accomplished with steroid and cyclosporine therapies. Twelve patients suffered 14 major complications, including perforated ulcer in 3 patients; pancreatitis in 3 patients; pneumatosis coli in 2 patients; and cholecystitis, colonic necrosis, appendicitis, incarcerated umbilical hernia, pancreatic abscess, and toxic epidermal necrolysis in 1 patient each. Aggressive management of the patients included laparotomy in all but 2 patients with mild pancreatitis and the patient with toxic epidermal necrolysis, who was treated as a patient with a severe burn. In all of the patients, there was a resolution of these complications, except in one 59-year-old man with fatal hemorrhagic pancreatitis. Eleven of the 14 complications occurred during the initial hospitalization. The fatal case of pancreatitis was 1 of 5 (9%) operative mortalities in the entire series. Fifty operative survivors have been followed up for an average of 19 months, with four late deaths (8%) related to rejection. The actuarial probability of survival in patients discharged from the hospital was 90% at 12, 24, and 48 months.

To determine whether acutely ischemic myocardium could be more effectively salvaged by reperfusion on cardiopulmonary bypass (CPB) in the cardioplegia-treated heart than with reperfusion in the beating, working heart, 52 greyhound dogs underwent 3 hours of left anterior descending (LAD) occlusion and were randomly assigned to one of four groups. In Group I (19 dogs) the LAD occlusion was released at 3 hours and reperfusion continued in the beating, working heart for an additional 3 hours. Group II (six dogs), Group III (14 dogs), and Group IV (13 dogs) were placed on CPB and underwent 45 minutes of hypothermic ischemic arrest protected by aortic root potassium cardioplegia. In Group II, only aortic root potassium cardioplegia was given; in Group III, the ischemic area was perfused with potassium cardioplegic solution via a graft from the internal mammary artery (IMA) to the LAD. In Group IV, blood cardioplegic solution via the IMA-LAD graft was used. After the cross-clamp and local occlusion were removed, CPB was discontinued after an additional 45 minutes and reperfusion was continued off CPB for an additional 1 1/2 hours (total 6 hours). The ischemic area at risk was determined by injecting monastryl blue dye via the left atrium while the LAD was briefly reoccluded. After the animal had been sacrificed and the left ventricle had been sectioned, the area of myocardial necrosis was determined by nonstaining with triphenyltetrazolium chloride (TTC). For each group, the ratios of area of necrosis/area at risk (AN/AR) were calculated and postreperfusion arrhythmias were documented. Postreperfusion arrhythmias were noted in 11 of 12 animals in the beating, working heart group and only two of 24 in the combined CPB groups. The mean AN/AR was 66% +/- 2% in the beating, working heart (Group I), 59% +/- 6% after infusion of potassium cardioplegic solution into the aortic root (Group II), 57% +/- 6% with blood cardioplegia (Group IV), and 38% +/- 6.5% after global and local application of the potassium cardioplegic solution into the ischemic area (Group III). This study suggests that the reperfused ischemic myocardium will sustain less necrosis and less postreperfusion arrhythmias when the heart is protected by global and local cold potassium cardioplegia on CPB.

Emergency operations for restoration of coronary artery blood flow are an effective means for treatment of unstable anginal syndromes. The risk of such operations is minimized by preoperative stabilization with medical therapy. Mechanical circulatory assistance may be a useful adjunct in some patients, especially in the presence of left main coronary obstruction. Utilization of emergency revascularization for patients with evolving myocardial infarction may be beneficial in some patients, but this approach remains controversial at present. Emergency revascularization for cardiogenic shock improves chances for survival in selected patients, and it may be combined with valve replacement, infarct resection, or repair of ruptured myocardium in patients with adequate residual contractile tissue.

Ten patients underwent mitral valve re-replacement for the third to sixth time through a right thoracotomy using one-lung anesthesia, femorofemoral bypass, profound systemic hypothermia, and low-flow perfusion without aortic cross-clamping or cardioplegia. The indications for this approach were previous mediastinitis, severe right ventricular hypertension with multiple previous sternotomies, intact coronary artery bypass graft, or previous aortic valve replacement. There was 1 operative death, which was due to end-stage pulmonary hypertension and intractable right heart failure. Blood loss was minimal, and there was no major postoperative morbidity in the 9 surviving patients except for supraventricular arrhythmias.

Mortality risk in coronary artery disease (CAD) is more closely related to angiographic findings of multiple coronary artery obstructions and left ventricular asynergy than to the severity of angina pectoris, the major symptom of CAD. Since coronary revascularization surgery is most frequently performed to relieve chest pain, there are few reports evaluating the results of coronary artery bypass surgery in patients with minimal or no angina pectoris but with anatomically severe disease. From July, 1970, through December, 1976, 844 patients had coronary artery bypass surgery performed at the Peter Bent Brigham Hospital for chronic or unstable angina pectoris. Twenty patients (2.3%) were operated on because of severe coronary obstruction but who had minimal or no angina. Fourteen patients underwent coronary arteriography because of a positive exercise tolerance test, and six because of a prior myocardial infarction. All but one patient had multivessel CAD, and four patients had significant left main coronary lesions. There was no operative mortality. One late death occurred 5 years postoperatively, for a 5.0% cumulative mortality. Average follow-up has been 34 months (range, 19 to 80 months). Of 12 patients with both pre- and postoperative exercise tests, eight have reverted to normal, and four show a less ischemic response to exercise. Coronary revascularization may have a beneficial effect on the patient with "asymptomatic" but anatomically severe CAD.

To determine whether coronary arteriograms accurately predict the presence of distal coronary lumena that are inadequate for bypass because of diffuse disease and/or small caliber, angiographic grading of distal lumen (DL) caliber was carried out on 867 diseased coronary arteries on which bypass was subsequently attempted. Where the DL was graded as normal, bypasses could be successfully constructed in 96% of cases. Where the general DL caliber was normal but one or more localized distal stenoses were present, bypasses could be successfully constructed in 95.6% of cases. Where the DL caliber was reduced to a mild-moderate degree angiographically, bypasses were successfully constructed in 83.6%. Where the DL had a severely reduced caliber or could not be visualized at all, bypasses were successfully constructed in 73.0%. Thus, even when a severely narrowed or totally occluded DL appears present, bypass can still be performed in almost 75% of cases. The angiographic diagnosis of a nongraftable distal segment is therefore unreliable and patients should not be denied bypass on this basis alone.

Three hundred thirty patients undergoing coronary bypass grafts for disabling angina, "preinfarction" angina, or coronary occlusion without cardiogenic shock have undergone coronary revascularization from July 1970 to March 1974. The operative mortality was 1.2 per cent and the long-term mortality, 4 per cent. Patients were subjected to life table analysis, and the figures suggest that in patients with two- and three-vessel coronary artery disease who received complete revascularization, there was a significant prolongation of life when compared with data from a large series of medically treated patients with angiographically documented coronary artery disease. Longer follow-up data will be important in definitively ascertaining the favorable effect of coronary revascularization on longevity.

The applicability of heart transplantation remains limited in part by the inability to preserve the excised heart for long periods of time. Free radical scavengers have been shown to protect the anoxic myocardium by preventing damage to the cell membrane and may, therefore, be effective in extending successful preservation of donor hearts. We perfused 10 sheep hearts for 8 hours in an ex vivo perfusion system. The effect of superoxide dismutase combined with catalase, 60,000 units/L, was studied in five sheep, and five received placebo. Control determinations and determinations after 8 hours of preservation were obtained with the heart perfused with autologous blood at 37 degrees C at an aortic perfusion pressure of 60 mm Hg and flow of 180 to 200 ml/min. After control readings, the hearts were arrested and perfused with a cold (6 degrees to 8 degrees C) oxygenated buffered crystalloid solution with or without superoxide dismutase and catalase at a perfusion pressure of 30 cm H2O for 8 hours. Left and right ventricular compliance was measured sequentially with separate intraventricular balloons. After 8 hours of ex vivo preservation, hearts receiving superoxide dismutase and catalase had significantly better left and right ventricular performance, higher myocardial oxygen consumption, and lower lactate production than the control group. The hearts preserved with superoxide dismutase and catalase showed significantly better left and right ventricular compliance, much less increase in heart weight, and no change in the diastolic pressures. The results suggest that superoxide dismutase combined with catalase may be effective in extending ex vivo preservation of hearts for cardiac transplantation.

The present study was undertaken to assess the effect of L-glutamate on the extended preservation of the heart ex vivo added to a hypothermic preservative solution. Ten sheep hearts were removed after application of cold crystalloid potassium cardioplegia. The hearts were immersed in iced normal saline and right ventricular and left ventricular intraventricular balloons were connected to transducers to measure compliance. Thermistor probes were placed in the interventricular septum. The heart was mounted on a retrograde perfusion apparatus via the cannula in the brachiocephalic trunk and placed in an isolated glass cylinder. The perfusion apparatus consisted of a roller pump, a heat exchanger, and a pediatric membrane oxygenator. Control determinations and those after 8 hr of preservation were made while the hearts were perfused with enriched autologous blood. Right and left ventricular compliance, left ventricular systolic and diastolic pressures, right ventricular systolic and diastolic pressures, left ventricular dP/dt, coronary arteriovenous oxygen consumption, lactate production, and heart weight were measured. Results showed significantly improved left and right ventricular systolic function with L-glutamate preservation. Whole heart oxygen consumption in the L-glutamate group showed a 4% increase, while the placebo group showed a significant decrease in oxygen consumption after 8 hr of preservation. The glutamate-preserved hearts also showed no change in lactate production after 8 hr of preservation as compared with a 81% increase in the placebo group. After 8 hr of perfusion there was 67% increase in the heart weight of the control and a 42% increase in the L-glutamate group.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluosol DA (20%), a perfluocarbon with high oxygen solubility, was administered by concurrent exchange transfusion (30 ml/kg) to anesthetized open-chested adult greyhounds (n = 9) 1 hour after left anterior descending coronary ligation. Mechanical ventilation using 100% oxygen was used throughout the experiment. A second similar group (n = 9) received 0.9% normal saline solution (30 ml/kg), and a third group (n = 9) received no further intervention. Systemic, right atrial, and left atrial pressures were not altered by the exchange transfusion. Monastryl blue dye was injected through the left atrial line at 6 hours after ligation to define the area of myocardium at risk (AR); the animals were then killed and the heart was excised. The left ventricle was sliced at 5 mm intervals and stained using triphenyltetrazolium chloride, defining areas of necrosis (AN). The ratio of AN/AR and total left ventricular mass were then compared with the use of planimetry. The results were as follows: the AN/AR ratio in the 9 control animals was 90 +/- 2 (mean +/- standard error of the mean); in the 9 animals who received saline solution it was 88 +/- 2; and in the animals who received Fluosol it was 67 +/- 4 (p less than 0.01 compared with control; p less than 0.001 compared with the saline group). Fluocarbon exchange transfusion may reduce infarct size when administered after coronary occlusion.

Improved assessment of valve area is essential to understanding the performance of prosthetic valves. The authors studied six patients undergoing aortic valve replacement using mechanical (ME) or porcine (PO) prostheses. Instantaneous cardiac output (CO) (L/min) was measured in the aorta using an ultrasonic flow probe. Left ventricular and aortic pressures (mmHg) were measured using Millar catheters. Data were analyzed using an IBM PC-AT. Valve area (cm2) was determined using Gorlin's formula (AG) and a new formula for instantaneous area derived mathematically and using a theoretic constant. AG, mean (AI) and peak (Apk) instantaneous areas were compared to geometric measures of area (Aactual) in vitro. Peak instantaneous area correlates best with measured area. Intraoperative assessment using the ultrasonic flow probe and computer analysis is helpful in understanding the dynamic properties of prosthetic valves in vivo.

Comparison of 1085 patients having coronary bypass surgery without cardioplegia from Jan. 1970 to Aug. 8, 1977 with 1060 patients operated upon with cardioplegia from Aug. 9, 1977 to Dec. 31, 1980 suggests that improved myocardial protection afforded by cardioplegia combined with profound topical hypothermia has its principal impact in those patients requiring urgent or emergency operations by reducing the probability of intraoperative left ventricular failure after coronary bypass. The need for postoperative balloon pumping and the risk of intraoperative death were significantly lower in patients operated upon with hypothermia + cardioplegia myocardial protection. In patients who survived 30 days after operation there was no significant improvement in long-term survival, incidence of myocardial infarction, or recurrence of angina pectoris in the cardioplegia group despite a greater average number of grafts per patient and a smaller number of ungrafted but obstructed coronary arteries.

Reliable aortic valve replacement was one of the most significant advances in the treatment of cardiac disease in this century. It allowed, for the first time, a reliable and reproducible method to palliate the symptoms of aortic stenosis and regurgitation and significantly improved longterm survival over that after medical treatment. Sporadic attempts at aortic valve replacement had been conducted in the late 1950s, but the pioneering work of Harken et al, followed by the final development of a reliable device by Starr, Edwards, and coworkers, opened the era of successful aortic valve replacement. We review the prognosis of patients following aortic valve replacement with aortic stenosis and regurgitation with and without associated procedures and evaluate the various types of bioprosthetic and prosthetic valves in current use, presenting advantages and disadvantages of each type of replacement device.

Patients with congenital cardiac shunts in whom marked functional disability, cyanosis and pulmonary arterial hypertension develop have been considered inoperable or at exceedingly high risk. Three adult patients, 2 with atrial septal defect (ASD) and 1 with patent ductus arteriosus (PDA), presented with New York Heart Association class IV symptoms, bidirectional shunting with cyanosis, polycythemia, severe pulmonary hypertension, and increased pulmonary vascular resistance. Pulmonary arterial pressure did not decrease in response to administration of 100% oxygen in any patient, and 2 had lung biopsy results showing advanced pulmonary vascular obstruction. While a right-to-left shunt caused cyanosis in all patients, the net shunt was left to right (Qp/Qs greater than 1) and the resistance ratio (Rp/Rs) less than 0.5. All 3 patients survived operation, became acyanotic with normal hematocrit, and are in functional class I or II a mean of 36 months postoperatively. At repeat cardiac catheterization, pulmonary arterial pressure and resistance had decreased substantially. This high-risk group of patients with bidirectional shunts, in whom cyanosis due to pulmonary vascular obstruction and polycythemia develop and who appear to be at very high operative risk, should still be considered for surgical correction if the usual criteria for operability exist: net left-to-right Qp/Qs and Rp/Rs less than 0.50.

To determine the operative survival rate following combined mitral valve replacement (MVR) and coronary artery bypass graft (CABG) operation, we evaluated 100 patients, who were seen consecutively at the Peter Bent Brigham and Brigham and Women's Hospital from 1972 to 1982. There were 63 men and 37 women; the mean age was 62 years. Thirty-six patients were in New York Heart Association (NYHA) Functional Class III, and 64 were in functional Class IV. Mitral regurgitation was predominant in 76 patients; mitral stenosis, in 24. Emergency operations were performed in 15 patients, and elective or semielective operations were performed in 85. There were 18 operative deaths (18%): 9 in patients having elective operations (10.5%) and 9 in those having emergency operations (60%; p less than 0.01). Significant preoperative factors related to operative death were NYHA functional class, increased pulmonary vascular resistance, lower cardiac index, and lower ejection fraction in the nonsurvivors. The rate of survival did not differ according to sex, age, or degree of coronary artery disease. In addition, myocardial protection with potassium cardioplegia and complete coronary revascularization significantly reduced operative mortality in the elective group of patients but did not alter the mortality in the emergency group.

A second case of malfunction of a Harken disk valve due to undue disk wear is reported. Two and one-half years after aortic and mitral valvular replacement, the patient had paraprosthetic aortic insufficiency and physical findings suggesting intermittent dysfunction of his prosthetic mitral valve. Catheterization showed intermittent hemodynamic abnormalities; fluoroscopic and cineangiographic findings indicated intermittent mitral regurgitation secondary to undue mitral disk wear. At operation, the excised valve showed normal struts and sewing ring but severe disk wear. There was loss of disk substance and rim notching.

Blood utilization in 400 consecutive adult patients undergoing a wide variety of cardiovascular operations requiring cardiopulmonary bypass was documented following institution of: 1) complete oxygenator hemodilution; 2) intraoperative phlebotomy and autologous transfusion; 3) infusion of residual oxygenator red cells; and 4) use of reconstituted frozen cells in patients whose blood type was uncommon. These techniques have resulted in an average utilization of 4.8 units of blood per adult patient. Fourteen patients required no blood at all and a total of 259 patients required less than 5 units of blood during their entire hospital course. Physiologic effects of this blood program and hemodilution were evaluated in ten patients and the results indicate that marked reduction of red cell mass by hemodilution with hypothermia and low flow perfusion is not detrimental to satisfactory whole blood oxygenation during open heart surgery.

Porcine aortic valve xenografts stabilized with glutaraldehyde have been implanted in 91 patients with acquired and congenital valvular heart disease. The indications for use of this valve have included age, previous sensitivity to anticoagulants, or a concomitant condition contraindicating anticoagulant therapy. There were two operative deaths and three late deaths in 44 mitral, 25 aortic, 16 aortic-mitral, 5 mitral-tricuspid, and one aortic-mitral-tricuspid replacements. There were no valve failures from cusp rupture, although one valve was replaced because of annular disproportion. There was one inhospital stroke but no late emboli in a 3 to 33 month followup period, 16.5; 72 patients are functional class 1, 10 class 2, and one patient is class 3. In appropriate patients this biologic tissue valve relieves the hemodynamic abnormalities of valvular heart disease, is associated with a low embolization rate without anticoagulant therapy and, to date, has been durable.

From January 1, 1972, to January 1, 1981, 1282 consecutive valve replacements were performed at the Peter Bent Brigham Hospital. Fifty-eight of these (4.5%) were rereplacements: 14 for prosthetic valve subacute bacterial endocarditis (SBE), 29 for primary valve dysfunction (PVD) and 15 for perivalvular leak (PVL). Aortic rereplacement was done in 27 patients (eight for SBE, 10 for PVD and nine for PVL) and mitral rereplacement in 31 patients (six for SBE, 19 for PVD and six for PVL). Twenty-six patients were in New York Heart Association functional class III and 32 were in class IV. Ten class IV patients underwent emergency valve replacement (three for SBE, two for PVD and five for PVL). The overall in-hospital mortality rate for valve rereplacement was 14% (eight of 58 patients). For mitral valve rereplacement it was 13% (four of 31), compared with 6.4% (19 of 295) for initial mitral valve replacement. For aortic valve rereplacement, the mortality rate was 15% (four of 27), compared with 5.2% (23 of 440) for initial aortic valve replacement. The cause of death was low cardiac output in six patients, hemorrhage in one patient and sepsis in one patient. All of the patients who died were in functional class IV (p = 0.018). The in-hospital risk for rereplacement of a dysfunctional aortic or mitral valve is no different from that for primary valve replacement unless the patient deteriorates to class IV and requires an emergent operation.

Reperfusion of ischemic tissue is responsible for production of metabolites with deleterious local vascular effects. Thromboxane A2, a potent vasoconstrictor and platelet aggregator, has been implicated as a mediator of the "reperfusion injury." We studied the effect of an experimental thromboxane synthetase inhibitor, OKY-046, on coronary sinus thromboxane levels, ventricular irritability, myocardial contractility, infarct salvage, and histologic features of reperfusion. Sixteen sheep were randomized to OKY-046, 3 mg/kg, or saline vehicle before 3-hour occlusion and subsequent reperfusion of the left anterior descending artery. The OKY group demonstrated less ventricular irritability as measured by incidence of ventricular fibrillation and necessity for countershock to reverse tachyarrhythmias. Coronary sinus thromboxane levels were significantly lower in the OKY group compared with the control group. There is additional evidence to suggest that OKY increases infarct salvage and attenuates histologic features of microcirculatory damage.

This study was conducted to assess the protective effects of antegrade infusion of cardioplegic solution with simultaneously controlled coronary sinus occlusion on regionally ischemic myocardium after acute coronary occlusion and reperfusion. Twelve sheep were subjected to 1 hour of occlusion of the distal left anterior descending coronary artery. Sheep in group I (n = 6) were subjected only to infusion of potassium crystalloid cardioplegic solution into the aortic root, whereas in group II (n = 6) a stitch was snared around the proximal coronary sinus for its subsequent occlusion during antegrade infusions of cardioplegic solution. All animals were placed on cardiopulmonary bypass. Five hundred milliliters of cardioplegic solution at 4 degrees to 8 degrees C was administered in three divided doses during the total cross-clamp period of 30 minutes. The occlusion of the left anterior descending artery was then released, and the animals were weaned from bypass and studied for an additional 4 hours. Coronary sinus pressure, myocardial temperature, regional function assessed by pairs of ultrasonic crystals, global function assessed by rate of rise of left ventricular pressure and cardiac output, and the area at risk and area of necrosis were determined. The heart was excised at the end of the experiment and stained. Animals treated by the technique of antegrade infusion combined with coronary sinus occlusion had more homogeneous myocardial cooling during cardioplegic infusions and better recovery of the first derivative of left ventricular pressure and regional segment shortening at 90 and 270 minutes of reperfusion than those treated with antegrade infusion alone (p less than 0.01 and p less than 0.05, respectively). The group treated by antegrade infusion of cardioplegic solution combined with coronary sinus occlusion had an area of necrosis/area at risk ratio of 40.5% +/- 1.2%; the antegrade infusion group, 58.3% +/- 4.1% (p less than 0.01). These data suggest that antegrade infusion combined with coronary sinus occlusion may be an improved method of global and regional myocardial protection in the presence of an occluded coronary artery.

Hemodilution is used frequently for patients undergoing elective coronary bypass surgery but relatively little is known about the effects of hemodilution on acute myocardial infarction. Left ventricular infarctions were planimetered after acute coronary occlusion in dogs treated with and without hemodilution. The control group was maintained at a normal hematocrit (40-45) while the intervention group was hemodiluted with 6% dextran in saline 30 min after left anterior descending coronary artery occlusion to a hematocrit less than 50% of control (20). Systemic arterial and left atrial pressure were maintained at control levels as were arterial pO2 and pH. Mean infarct size in the control group was 20.72 +/- 1.38% (SEM) of the left ventricle while the hemodiluted group had a mean infarct size of 18.80 +/- 2.11% of the left ventricle. Reduction of red cell mass to less than 50% of normal does not increase the size of myocardial infarction after acute coronary artery occlusion suggesting that oxygen supply to ischemic areas is maintained if systemic hypoxia is prevented.

Although the internal mammary artery bypass seems an ideal coronary bypass vessel, it has not usually been possible to use this vessel to bypass distal lesions in the right coronary circulation. In this experiment, the right internal mammary artery was utilized in retrograde fashion to evaluate this anatomically more suitable vessel as a bypass graft to the occluded right coronary artery in the dog. Reversal of acute myocardial ischemia was demonstrated by mapping epicardial ST-segment elevation and measuring surface pH. Preliminary long-term experiments have also demonstrated patency and perfusion of the distal right coronary artery by this method.

The effects of prostacyclin (PGI2) with and without heparin were studied in 28 dogs that underwent 2 hours of cardiopulmonary bypass. Five groups were created: group I (six dogs) received heparin, 1.25 mg/kg; group II (six dogs) received low-dose heparin, 0.5 mg/kg, and PGI2, 500 ng/kg/min; group III (six dogs) received low-dose heparin alone; group IV (four dogs) received PGI2, 500--1000 ng/kg/min; and group V (six dogs) received ibuprofen, 12.5 mg/kg, dipyridamole, 1 mg/kg, PGI2, 20 ng/kg/min, and low-dose heparin. Significant clot deposition occurred in the oxygenators in groups III, IV and V. Platelet counts decreased to a mean of 36.8 +/- 5.7% (+/- SEM) of control in group I, which had normal clinical heparin dose for dogs, but to only 74 +/- 7% of control in group II. This improvement was significant (p less than 0.005). Platelet aggregation induced by adenosine diphosphate 60 minutes after CPB showed poor aggregation in group I but almost normal aggregation in group II. Protamine was unnecessary in groups that received PGI2. PGI2 in combination with low-dose heparin provides adequate anticoagulation during cardiopulmonary bypass in dogs, preserves platelet number and function and is associated with minimal postoperative bleeding.

Ninety-four cardiac operations were performed on 92 patients 65 years of age and over at the Peter Bent Brigham Hospital, Boston, from July 1970 to July 1974. There were 39 aortic valve replacements, 11 mitral valve replacements, 14 double valve operations, 16 coronary revascularizations, five repairs of aortic dissections, and one atrial septal defect closure. The operative mortality was 11 percent in elective cases and 40 percent in the emergency cases, an overall mortality of 17 percent. There were no hospital deaths following elective double valve operations or coronary bypass procedures. Combined hospital and late mortality of ventricular aneurysmectomy approached 100 percent. Myocardial infarction accounted for eight of the 16 hospital deaths. The overall late mortality has been 7.5 percent. Ninety-seven percent of surviving patients are functional class 1 or 2 with a follow-up of 4 to 48 months. These data suggest that any necessary cardiac surgery, excepting ventricular aneurysmectomies, may be performed electively with low risk and a high likelihood of satisfactory rehabilitation in the elderly age group. The major determinants of mortality are the urgency of the intervention and associated coronary artery disease.

The magnitude and distribution of myocardial blood flow through a saphenous vein (SV) bypass graft and an internal mammary artery (IMA) graft (diameter greater than or equal to 2 mm) into the same left anterior descending coronary artery (LAD) (diameter congruent to 1.5 mm) were determined at rest, with atrial pacing, and with elevated left ventricular end-diastolic pressure (LVEDP) in 18 dogs. Blood flows through the native LAD, SV, and IMA grafts were similar in the resting heart. With atrial pacing (heart rate = 150% of control), flow in both the SV and IMA grafts increased but the difference was not significant. With elevated LVEDP (20 mm Hg) produced by transfusion, flow in both SV and IMA grafts increased, but, again, these increases were not significantly different. The SV and IMA bypass grafts have similar flow rates at rest and during increased functional demand, provided the grafts are larger than the vessels into which they are placed.

We investigated the effect of different forms of myocardial protection on infarct size and on the necrotic myocardial process after reperfusion for acute occlusion of the left anterior descending coronary artery (LAD) in dogs. Three control groups were formed: a 1 hour, 2 hour, and 6 hour locally ischemic control. Three experimental groups were locally ischemic for 1 hour and then reperfused after an additional hour of local ischemia on cardiopulmonary bypass with the heart protected by intermittent ischemia, cold potassium cardioplegia, or blood cardioplegia. To delineate the area at risk, the LAD was temporarily occluded 30 seconds before the 6 hour sacrifice time, and monastral blue dye was injected through a polyvinyl catheter placed in the left atrial appendage. The LAD area at risk (AR) was not stained. After 6 hours the heart was excised and treated with triphenyltetrazolium chloride (TTC) to define the area of myocardial necrosis (AN). The AN/AR ratio was determined for each animal by planimetry. Mean values were then computed in each of the six groups and evaluated by the Student's t test for paired data. The 1 hour control group had an AN/AR ratio of 64% +/- 5%; the 2 hour control group, 80% +/- 6%; and the 6 hour control group, 92% +/- 1%. The intermittent ischemia group had an AN/AR ratio of 83% +/- 2%; the crystalloid cardioplegic group (2 hours of ischemia) had a ratio of 69% +/- 4%, similar to the 1 hour control but significantly smaller than the 2 hour control (p less than 0.05); and the blood cardioplegia group had an AN/AR ratio of 48% +/- 8%, significantly better than any other group. These data demonstrate that myocardial necrosis after coronary occlusion is a time-related phenomenon and will increase to encompass a large fraction of the area at risk unless there is physical or pharmacologic modification during reperfusion, such as crystalloid or blood cardioplegia.

This report relates the postoperative clinical and cineangiographic status of 67 patients selected from a total of 202 patients who underwent coronary artery surgery at the Peter Bent Brigham Hospital from July, 1970, to July, 1972. The mean interval after operation was 12.6 months. Ninety-one per cent of the 67 patients were improved from their preoperative status. Forty-eight patients (71 per cent) were studied to evaluate recurrence of mild to moderate angina or occurrence of interval myocardial infarction, and 19 patients (29 per cent) were entirely asymptomatic. In the 67 patients studied, 112 coronary arteries received a total of 115 grafts. (There were 89 ungrafted coronary arteries.) Total graft patency rate for the 58 patients in whom angina was totally or significantly relieved was 65 per cent. However, one or more grafts were patent in 52 (90 per cent) of these 58 patients. In grafted arteries, progression was found in segments proximal to the graft in 37 per cent of arteries, at the site of anastomosis in 10 per cent, and distal to the site of anastomosis in 17 per cent. The frequency of obstruction distal to the site of anastomosis was not significantly different from the frequency of progression in nongrafted arteries, in contrast to preliminary data from this laboratory. Overall and regional progression in grafted arteries appeared to occur primarily within the first four months after surgery and was found, thereafter, in a constand percentage of vessels studied. Progression in coronary arteries was independent of patency or occlusion of the graft to the vessel. It is hypothesized that while proximal progression is probably a consequence of altered hydraulic factors, distal lesions seem to represent natural progression of atherosclerotic disease.

In our Division of Cardiothoracic Surgery between 1970 and 1982, 110 patients (88 males and 22 females) had coronary artery bypass grafts (CABG) performed for unstable angina pectoris after acute transmural myocardial infarction. Fifty-one patients (mean age 59 years) had CABG within 2 weeks of myocardial infarction (Group 1); and 59 patients (mean age 56 years) (p = NS) within 6 weeks of myocardial infarction (Group 2). The incidence of preoperative arrhythmias, left ventricular ejection fraction, end-diastolic pressure, and the number of vessels diseased were similar in Groups 1 and 2. The incidence of cardiogenic shock was higher in Group 1 (16/51, 31% vs 2/59, 3% [p < 0.001]). This was also the case with the use of the intraaortic balloon (32/51, 63% vs 12/59, 20% [p < 0.001]), and the need for emergency operation (29/51, 57% vs 4/59, 7% [p < 0.001]). The mean number of grafts was 2.8 in Group 1 and 3.0 in Group 2 (p = NS). Operative mortality was 20% (10/51) in Group 1 and 7% (4/59) in Group 2 (p < 0.01). Excluding patients in cardiogenic shock, operative mortality was 0% (0/35) in Group 1 and 5% (3/57) in Group 2 (p = NS). Incidences of late death, recurrent angina, and permanent disability were similar during mean follow-up times of 3.2 years in Group 1 and 4.1 years in Group 2. Actuarial probability of survival was 96% at 1 year and 83% at 5 years. Myocardial revascularization early after transmural myocardial infarction has a low risk, especially in the absence of cardiogenic shock. These results justify an aggressive approach to unstable angina, including patients within 2 weeks of transmural infarction.

This report describes the diagnosis and surgical treatment of a 48 year old patient with congenital right pulmonary arterial ostial stenosis, no intra- or extracardiac shunts and systemic levels of pressure in the main and left pulmonary artery with pulmonary vascular obstruction in the left lung. Operation consisted of a bypass graft of 10 mm woven Dacron from the main pulmonary artery to the distal right pulmonary artery producing an immediate 50 percent reduction in mean left pulmonary arterial pressure. Late postoperative evaluation revealed equal perfusion of both lungs, maintenance of the reduced pulmonary arterial pressure and improvement from New York Heart Association functional class IV to class I.

Mitral valve repair has been increasingly used at our hospital for mitral regurgitation with and without coronary disease. From January, 1984, to June, 1987, of 338 patients undergoing all forms of mitral valve surgery, 140 had first-time surgery for pure mitral regurgitation: 75 had valve repair, and 65 had valve replacement. Thirty-three of 75 (44%) had concomitant coronary bypass in the repair group, while 21 of 65 (32%) had coronary bypass in the replacement group. The mean functional class (3.4 versus 3.5), age (60 versus 61 years), and preoperative hemodynamics were similar in both groups. The cause of mitral regurgitation in the repair group was myxomatous change in 32 patients, ischemia in 27, rheumatic valve disease in 12, and endocarditis in 4. A Carpentier ring was used in 46, a Duran ring was used in 11, and none was used in 18. The operative mortality was 3 of 75 patients (4%) in the repair group, all with coronary artery bypass grafting, versus 2 of 65 patients (3%) in the replacement group, 1 of whom had undergone coronary artery bypass grafting. The mean postoperative functional class 15 months postoperatively was 1.12 in the repair group versus 1.15 in the replacement group. There were 7 late deaths in the replacement group and only 3 late deaths in the repair group. Actuarial survival at 30 months was 85 +/- 6% for the replacement group and 94 +/- 4% for the repair group. There were 5 late emboli (1 fatal, 4 nonfatal) after valve replacement and none after valve repair (p = 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)