Value of early postoperative epicardial programmed ventricular stimulation studies after surgery for ventricular tachyarrhythmias.

The value of early postoperative epicardial programmed ventricular stimulation studies after electrophysiologically-directed surgery for ventricular tachyarrhythmia was assessed in 34 patients who underwent epicardial stimulation within 7 to 30 days (mean 9.8) of surgery and were followed up for at least 6 months. The antiarrhythmic operation performed was an endocardial ventriculotomy (full encircling or limited), an endocardial resection, a wall resection or a combination of these procedures. All these interventions were directed by intraoperative mapping during sinus rhythm. Temporary epicardial wire electrodes left at the time of surgery rather than endocardial catheter electrodes were used to perform the pacing. The stimulation protocol included the introduction of up to three ventricular extrastimuli and incremental burst ventricular pacing performed at twice diastolic threshold (9.2 +/- 5.8 mA for the right ventricle and 6.0 +/- 3.5 mA for the left ventricle). A study was considered positive when ventricular tachycardia, defined as 10 or more consecutive ventricular beats, was induced by any pacing modality. Nineteen patients (Group I) had a negative study: after stimulation of both ventricles in 15 patients and of the left ventricle only in 4. Fifteen patients (Group II) had a positive study: after stimulation of the right ventricle in nine patients and of the left ventricle in six. The two groups were comparable with respect to preoperative clinical status, surgical procedures performed and postoperative ejection fraction. No arrhythmic events were observed in Group I during a mean follow-up period of 19.5 months (range 4 to 37), whereas seven arrhythmic events (47% incidence) occurred (p = 0.0008) in Group II during a mean follow-up period of 17.7 months (range 5 to 39).(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of morbid events and risk factors for death after cardiac transplantation.

Risk factors for death after cardiac transplantation performed at the University of Alabama at Birmingham from January 1981 to July 1985 included (by multivariate analysis) higher calculated preoperative pulmonary vascular resistance (early and constant phases), morphology of cardiomyopathy (versus ischemic heart disease) (constant phase only) and black race (constant phase). Overall actuarial survival was 71% at 1 year and 48% at 3 years (including azathioprine and cyclosporine eras). The hazard function for death was highest immediately after operation and declined rapidly thereafter, merging with a constant phase of risk at about 3 months. The most favorable group for long-term survival was the group of white patients with ischemic heart disease and low pulmonary vascular resistance. When such patients had a pulmonary vascular resistance less than 3 units.m2, the 3 year survival rate exceeded 85%. The most common causes of death were acute rejection (24%) and infection (17%). The risk of infection remained highest during the first several months after any period of augmented immunosuppression.

Cognitive function after coronary bypass surgery: effect of decreased cerebral blood flow.

The effect of regional cerebral blood flow during coronary bypass surgery on performance on the Mini-Mental State Examination was studied in 14 patients. No association between lowered regional cerebral blood flow and cognitive scores was found.

Adult human valve dimensions and their surgical significance.

After cardiac valve replacement, some patients may show little improvement in functional status, in part because their prosthesis is restrictive. Guidelines were sought for valve replacement from measurements of valve circumference and calculated circularized orifice area in 160 postmortem hearts from adults with and without congestive cardiac failure. Multivariate analysis was used to relate valve area to age, sex, height, body surface area and cardiac failure. Only sex and cardiac failure were significantly related to valve area. Body surface area and other variables were poorly related to valve area. The mean (+/- standard deviation) circularized orifice area for adult male (M) and female (F) heart valves in the absence of cardiac failure were: Aortic, M 4.81 +/- 1.30, F 3.73 +/- 0.98; pulmonary, M 4.88 +/- 1.25, F 4.32 +/- 1.03; mitral, M 8.70 +/- 2.08, F 6.94 +/- 1.41; and tricuspid, M 11.9 +/- 2.72, F 9.33 +/- 2.02. In cardiac failure, atrioventricular valves enlarge (p less than 0.004). Guided by these dimensions, the surgeon can aim to insert a prosthesis of appropriate size. Comparison of these sizes with the manufacturer's calculated area for current prostheses shows that most mechanical valves and bioprostheses are potentially restrictive at rest. Improved prosthestic design, valve repair whenever possible, and anular enlargement procedures would be required to eliminate this size disparity.

Tricuspid atresia in adults.

Congenital atresia of the tricuspid valve is still uncommon in adult patients. However, increasingly successful palliative surgery in children now has increased its incidence after age 15 years. This investigation updates the clinical features of this disease in adults in light of modern diagnostic and surgical techniques. The data on all 18 adults with tricuspid atresia having angiography after age 15 years at this institution since 1970 were reviewed. The patients' ages ranged up to 45 years; 12 had had previous palliative surgery. Left cineventriculography, particularly biplane, with the long axial view (60 degrees left anterior oblique with cranial angulation) is the most important diagnostic mode and reveals the ventricular and great vessel relations. According to standard classification, 11 patients had type I anatomy (normal great arterial relations), 4 type II (transposed great arteries) and 2 type III ("corrected transposition of the great arteries"). One patient with inverted ventricles could not be classified. Associated additional congenital defects were uncommon. On the basis of these data, a new anatomic classification of tricuspid atresia is given which encompasses all possible atrial-ventricular-great arterial combinations. Seven patients had further surgery after study, including two procedures of the Fontan type (right atrium to pulmonary arterial conduit). Follow-up data on all 18 patients revealed two deaths (one early after operation, one late after study without further surgery). The remaining 16 patients survive 2 to 120 months after study. Four patients had naturally balanced pulmonary and systemic circulations and have survived to ages 21 to 41 years without surgery. Prudent surgical decision based on accurate anatomic diagnosis and the need for optimal effective pulmonary blood flow may result in a relatively optimistic prognosis in adults with this disease.

Pathogenesis of paroxysmal hypertension developing during and after coronary bypass surgery: a study of hemodynamic and humoral factors.

A prospective study of hypertension first appearing during and after saphenous vein bypass coronary surgery was performed in 28 patients to examine the incidence, hemodynamics and mechanism of this problem. In 15 patients (54 percent) new hypertension developed (mean arterial pressure greater than 107 mm Hg), characterized by increased peripheral vascular resistance and unchanged cardiac output within 1 hour after surgery. These 15 patients had a longer history of angina of greater severity, but also had relatively well preserved ventricular myocardium. Because plasma renin activity was depressed in patients in the hypertensive group, activation of the renin-angiotensin system was not important in the pathogenesis of this postoperative hypertension. The expected decrease in total peripheral resistance at the onset of cardiopulmonary bypass was observed in all patients, but later during bypass the peripheral resistance increased in all patients in association with a rise in plasma epinephrine levels. Patients who had hypertension postoperatively had a greater increase in arterial pressure and total peripheral resistance during cardiopulmonary bypass than did those with normal postoperative blood pressure. An elevation in plasma epinephrine and norepinephrine concentration, suggesting enhanced sympathoadrenal responsiveness to the challenge of cardiopulmonary bypass, was characteristic of the hypertensive group. This evidence of enhanced sympathetic activity during surgery may be a useful predictor of the development of postoperative hypertension.

Clotted hemopericardium with the hemodynamic characteristics of constrictive pericarditis.

Cardiac catheterization in a patient 4 weeks after coronary arterial bypass surgery demonstrated the typical hemodynamic findings of constrictive pericarditis, which completely resolved after removal of 500 ml of clotted pericardial blood. The pericardium was not responsible for the findings because it was left in place. This case demonstrates that clotted hemopericardium may mimic constrictive pericarditis.

Elevated catecholamines during cardiac surgery: consequences of reperfusion of the postarrested heart.

This study determines whether reperfusion of the heart with elevated blood levels of epinephrine (E) and norepinephrine (NE) during cardiac surgery produces deleterious effects. The study was conducted in 60 patients undergoing coronary artery bypass surgery. Arterial catecholamine values increased significantly (p less than 0.05), from prebypass control levels of 152 +/- 29 and 327 +/- 30 pg/ml of E and NE, respectively, to 415 +/- 78 and 554 +/- 49 pg/ml, at initiation of perfusion of the heart after the aortic cross-clamp was removed. Serial measurement of arterial (A) and coronary sinus (CS) E, NE, potassium, lactate, PO2 and CK-MB revealed that during 10 minutes of reperfusion the heart extracted E (positive A-CS difference, p less than 0.05), but that the NE A-CS difference was 0. The CS effluent contained significantly (p less than 0.05) higher concentrations of potassium, lactate and CK-MB during reperfusion than before aortic occlusion. There was no significant correlation of arterial E and NE, CS E and NE or A-CS differences in E and NE with myocardial release of lactate, potassium or CK-MB. There was a weak association (r = 0.4, p less than 0.01) between coronary sinus CK-MB and aortic occlusion time. Maximal arterial E and NE values did not correlate with 10-hour postoperative (maximal) CK-MB values. These results indicate that reperfusion of the postarrested ischemic heart with high levels of endogenously released catecholamines does not worsen ischemia or contribute significantly to myocardial damage.

Blood group compatibility and aortic valve allotransplantation in man.

Immunologic injury is an important contributing factor in failure of aortic valve allografts. The etiology of this immune reaction is unknown, but blood group antibodies have been postulated. In 46 patients, ABO and rhesus blood group compatibility bore no relationship between the success or failure or aortic valve allotransplantation. Therefore, circulating blood group antibodies do not contribute to valve failure, and recipients do not have to receive aortic valve allografts matched for ABO or rhesus compatibility.

Evaluating techniques of myocardial preservation for aortic valve replacement: operative risk.

In a two-year period 105 patients underwent isolated aortic valve replacement without hospital death. Eighty-three patients were operated on using hypothermic ischemic arrest; 22 patients had coronary perfusion. The early postoperative cardiac performance and incidence of complications did not differ between groups, although cardiopulmonary bypass time was shorter in the ischemic arrest group. These data suggest that ischemic arrest is a satisfactory method for myocardial preservation. However, because of the low hospital mortality rate with either method, these results and those of others cannot be taken to indicate the superiority of any method of myocardial preservation.

Surgical treatment for closed thoracic aortic injuries.

Eighteen patients with acute aortic tear secondary to nonpenetrating thoracic trauma and seven with chronic tears have been operated upon. Of the patients with acute injury, 28% had normal chest x-ray on admission. The diagnosis of acute aortic tear was made by aortography in all patients. Two patients died from causes unrelated to the aortic injury. In the group of 18 patients in which some method of perfusing the distal aorta was used, two developed paraplegia; in the group of 7 treated with simple aortic cross-clamping none occurred. The average aortic cross-clamp time 69 and 23 minutes, respectively, and average blood administration 3,139 and 1,700 ml., respectively. We conclude that the diagnosis of acute aortic tear cannot be reliably made on clinical grounds, and that with properly trained personnel the method of choice is usually simple aortic cross-clamping during repair.

Paradoxical septal motion in a patient with pulmonic stenosis.

This case will demonstrate abnormal (paradoxical) septal motion in a 31-year-old woman with an isolated pulmonary valvular stenosis. The right ventricular volume overload was exluded by the shunt series, special angiographic studies and at surgery. The echocardiographic abnormality persisted during a restudy three months after surgery.

Hemodynamic responses to dopamine infusion at controlled normal and low cardiac output states in the anesthetized dog.

In order to isolate the renal and pulmonary vascular effects of dopamine, we employed a dog preparation utilizing fixed venous return in order to control cardiac output at either a normal or low flow state. Dopamine infusion was carried out at doses of 8 and 16 microng/Kg./min. Heart rate, mean systemic arterial pressure, mean pulmonary artery pressure, and renal blood flow were measured. Changes in mean systemic arterial pressure, mean pulmonary artery pressure, and renal blood flow were not significant at either doses of dopamine. There was a dose-related increase in heart rate, most significant with a dose of 16 microng/Kg./min. and low cardiac output. No evidence was found to substantiate the existence of a specific dopaminergic receptor in the renal vasculature when cardiac output was controlled.

Use of temporarily placed epicardial atrial wire electrodes for the diagnosis and treatment of cardiac arrhythmias following open-heart surgery.

We retrospectively assessed our experience with the use of bipolar atrial epicardial electrodes in 70 consecutive patients following open-heart surgery. These patients, representing 1 month's experience on one of our cardiac surgical services, are a random sample of our total experience with more than 6.000 patients in whom we have routinely placed such electrodes. The atrial wire electrodes were used diagnostically and/or therapeutically in 57 patients a total of 139 times. In only 13 patients were the atrial wires not used for any reason. Atrial electrograms were recorded 63 times in 34 patients, 41 times to establish a diagnosis of an arrhythmia and 22 times to confirm the diagnosis of an arrhythmia originally suspected from interpretation of a standard or monitor electrocardiogram (ECG). Atrial pacing was used to treat abnormalities of rhythm or conduction or both in 75 instances in 49 of the 70 patients. Because of their great utility in the diagnosis and treatment of arrhythmias, we conclude that routine placement of atrial wire electrodes at the time of operation is indicated regardless of the nature of the open-heart procedure or the preoperative rhythm.

Incremental risk factors for spinal cord injury following operation for acute traumatic aortic transection.

Of 35 patients operated upon for acute traumatic transection of the upper descending thoracic aorta between 1967 and March 31, 1980, 33 had sufficient information for us to analyze the incidence of spinal cord injury (paraplegia or paresis). This event occurred in eight patients. Multivariate analyses indicated that spinal cord injury was more likely to occur with long aortic cross-clamp times (p = 0.08) when no shunt was employed to perfuse the distal aorta during cross-clamping. The data suggest that if an aortic cross-clamp time exceeding about 30 minutes is anticipated, a shunt should be employed during aortic cross-clamping.

Late results after mitral valve replacement with the Björk-Shiley and porcine prostheses.

The late results of isolated mitral valve replacement were retrospectively evaluated in 357 patients receiving a Björk-Shiley (B-S) tilting disc prosthesis and 96 patients receiving a porcine bioprosthesis (PB) (Vascor or Carpentier-Edwards) between March, 1973, and July, 1978. The groups were comparable with regard to age, sex, New York Heart Association functional class, preoperative cardiac rhythm (sinus or atrial fibrillation), left atrial size (normal or enlarged), and presence of thrombus in the left atrium at operation. All of the B-S and 14 of the PB patients received long-term anticoagulant therapy. The median duration of follow-up was 46 months in the B-S group and 32 months in the PB group. At 5 years, survival was 70% for the B-S and 68% for the PB groups (NS). The percentage of patients free of thromboembolic episodes was 77% for the B-S and 78% for the PB groups (NS). Fifty-six percent of the B-S and 49% of the PB patients were alive and free of thromboembolism, complications related to anticoagulant therapy, or other valve-related complications (dehiscence, degeneration, or endocarditis) (NS). The presence of atrial fibrillation, enlarged left atrium, preoperative thromboembolic episodes, and left atrial thrombus had no effect on the incidence of thromboembolic complications with either prosthesis. From this analysis, it appears that the major advantage of the PB over the B-S prosthesis is its use in patients in whom long-term anticoagulation is contraindicated.

A comparison of repair and replacement for mitral valve incompetence.

A total of 101 reparative and 389 valve replacement operations, isolated or combined with tricuspid annuloplasty or operations for coronary artery disease, were done for mitral incompetence (1975 to July 1, 1983). The patients undergoing repair as a group were younger and had less hemodynamic and functional derangement than those undergoing replacement. The prevalence of repair was less (p less than 0.001) for two surgeons than for the other four, even when possible differences in patient populations were taken into account by multivariate analysis. Five-year survival rate, including hospital deaths, was 76% after valve repair and 56% after valve replacement (p = 0.005). However, by multivariate analysis, valve replacement rather than repair was only possibly (p = 0.14) a risk factor. (Multivariate analysis in all patients undergoing mitral valve repair in the period 1967 to 1985 [n = 210] did not find the type of annuloplasty to be a risk factor.) The incidence of reoperation was no different after repair or replacement and there was no increase in the risk of reoperation late after repair. Endocarditis early or late after operation occurred in 11 of the 389 patients undergoing mitral replacement and in none of those undergoing repair (p = 0.08). The functional status of the patients was not different between the two groups. These data, and the experience of others, indicate the advantages of repairing rather than replacing the incompetent mitral valve whenever possible.

In vitro effects of aprotinin on activated clotting time measured with different activators.

The effects in vitro of aprotinin on the activated clotting time measured with both celite- and kaolin-activated tubes were investigated in 21 consecutive patients requiring cardiopulmonary bypass. Four whole-blood samples (2 ml per sample) from each patient were tested simultaneously with Hemochron automated timing systems (International Technidyne Corp., Edison, N.J.) before, during, and after cardiopulmonary bypass. One tenth milliliter of either aprotinin (at a final concentration of 80, 120, or 180 KIU/ml) or saline solution was mixed in vitro with blood samples before determination of the activated clotting time. Aprotinin had no inhibitory effect on the activated clotting times of unheparinized blood. After heparin administration, aprotinin in the above concentrations prolonged the activated clotting times measured with celite-activated tubes by 47% to 71%, as compared with the measurements of the activated clotting time without the addition of aprotinin. The activated clotting times in kaolin-activated tubes were not increased, however, by the in vitro addition of aprotinin. Our in vitro results indicate that aprotinin in concentrations from 80 to 180 KIU/ml does not significantly enhance the inhibitory effects of heparin on the intrinsic coagulation system as evaluated by measurement of the activated clotting times in kaolin-activated tubes. The anticoagulation effect of heparin in patients receiving aprotinin infusion should be monitored with kaolin-activated instead of celite-activated tubes because the celite makes the measured activated clotting time unreliable in patients receiving aprotinin therapy. These in vitro results require confirmation in vivo in patients receiving aprotinin therapy.

Myocardial distribution of cardioplegic solution after retrograde delivery in patients undergoing cardiac surgical procedures.

The myocardial distribution of both antegrade and retrograde cardioplegia for cardiac surgical intervention, after induction of cardioplegia via the aortic root, was directly assessed and compared in 19 patients by means of contrast echocardiography. Two-dimensional transesophageal echocardiographic images of the short axis of the left ventricle at the level of the papillary muscles were obtained after sonicated Renografin-76 microbubbles were injected into an aortic root and/or transatrial coronary sinus catheter during delivery of cardioplegic solution. Segmental distribution of cardioplegic solution was immediately noted in the myocardium at the time of contrast injections. In 11 of 18 patients (61%) cardioplegic solution was dispersed to all left ventricular myocardial segments after antegrade delivery. In 17 of 19 patients (90%) retrogradely delivered cardioplegic solution (after antegrade induction of cardioplegia in 18 of the 19 patients) was dispersed to all the left ventricular myocardial segments, including the septum. In 2 of the patients, initial lack of retrograde distribution of cardioplegic solution was remedied when the coronary sinus catheter was repositioned and contrast cardioplegic solution was reinjected. Imaging of the right ventricle was possible in only 4 of the 19 patients and revealed that after retrograde delivery, cardioplegic solution had been at least partially distributed to the right ventricle as well. We performed off-line videodensitometric analysis in 9 patients after retrograde delivery of cardioplegic solution. Mean peak pixel-intensity ratio of flow from the endocardium to the epicardium in the left ventricular free wall was 1.46 +/- 0.27, and mean peak pixel-intensity ratio of flow from the left to the right intraventricular septal endocardium was 1.39 +/- 0.33 (p < or = 0.05).

Hospital mortality of re-replacement of the aortic valve. Incremental risk factors.

A total of 200 aortic vale re-replacements were performed between Jan. 1, 1975, and July 1, 1979. The re-replacements (RRP) were an isolated procedure or combined with coronary artery bypass grafting or resection of ascending aortic aneurysm. Ten patients (5%) died in hospital, compared with 24 (2.9%) among 842 patients undergoing isolated or combined initial aortic valve replacement (AVR) (p = 0.12). The mode of death was cardiac failure in six of the 10 patients, hemorrhage in two (from accidents at repeat sternotomy), and neurologic deficits in two (each with innominate vein transection at repeat sternotomy repaired by ligation). There were seven (3.9%) hospital deaths among 181 first RRP (p for difference from initial AVR = 0.5), but three (15%) of 19 died after the second or third RRP (p = 0.001). By simple contingency table analysis, preoperative New York Heart Association (NYHA) Class IV increased the risk of hospital death after RRP (p = 0.002), as did prosthetic valve endocarditis (p = 0.0005) and the use of cold ischemic arrest (p = 0.03). Logistic multivariate analysis showed advanced NYHA functional class (p = 0.02), use of cold ischemic arrest (p = 0.09), and increased aortic cross-clamps time (p = 0.03) to be incremental risk factors. Recommendations for reducing hospital deaths in the event of RRP are (1) reoperate before severe hemodynamic deterioration occurs, (2) plan and conduct the operation to minimize accidents from repeat sternotomy and dissection, (3) keep aortic cross-clamp time as short as possible, and (4) employ cold cardioplegia.