Postoperative exercise tolerance after aortic valve replacement by small-size prosthesis: functional consequence of small-size aortic prosthesis.

OBJECTIVES: The objective of this study was to determine whether a small-size valve prosthesis contributes to exercise intolerance, as assessed by VO2 measurement during an exhaustive cycle ergometer exercise. BACKGROUND: The determinants of exercise capacity after mechanical aortic replacement are not well known. The selection of small valve sizes has, however, been described as an independent predictor of exercise intolerance as assessed by exercise duration. Maximal oxygen uptake (VO2max) is a good index of exercise tolerance. METHODS: Fourteen patients were eligible, with a mean age of 62 +/- 6 years. Before surgery, the mean left ventricular ejection fraction (LVEF) was 73 +/- 8%. Two valve types with small diameter (19 to 21 mm) were used: Medtronic Hall and St Jude Medical. A healthy sedentary control group (n = 14) paired for age, weight and size was constituted. After one year of follow-up, cardiorespiratory tests were performed. In addition, the gradients through the prostheses were determined by continuous pulse Doppler at rest and immediately after the cardiorespiratory test. RESULTS The exercise tolerance was not significantly different between the control group and patient group: VO2 peak (21.7 vs. 20.4 ml/kg/min; p = 0.42), workloads (115 vs. 93 W; p = 0.13) and ventilatory parameters were similar. The mean and peak gradients at rest and during exercise were not correlated with VO2max. CONCLUSIONS: Valve replacement by small aortic prosthesis does not seem to be a factor of exercise intolerance as assessed by VO2max in patients without LVEF dysfunction before surgery.

Fibrin sealant for early repair of acquired ventricular septal defect.

The trend toward early operation for acquired ventricular septal defects exposes the patient to major perioperative bleeding and residual shunt because of the fragility of the recently necrosed myocardium. To reduce these complications we have used a fibrin sealant to reinforce the cardiac tissues in addition to the usual closure of the defect with a Dacron patch through a left ventricular septum around the defect, area. During cardiac arrest fibrin sealant is applied on the ventricular septum around the defect, between the septum and the patch, and on the edges of the ventriculotomy. This technique was used in three patients (mean age 68.2 years) operated on for an acquired ventricular septal defect within 4 days of the infarction and within 24 hours of the occurrence of the defect. Low postoperative bleeding, absence of recurrent shunt, and good ventricular function indicated satisfactory surgical result in all three patients. We suggest that the use of fibrin sealant during operations for acquired ventricular septal defects, by reinforcing the necrotic and fragile tissues, may reduce perioperative bleeding and assure a more solid implantation of the patch.

Comparison of myoglobin and creatine kinase MB levels in the evaluation of myocardial injury after cardiac operations.

Myoglobin was studied in 40 patients before, during, and after cardiac operations and was compared to the MB isoenzyme of creatine kinase to identify its possible role as a marker of perioperative myocardial damage. Myoglobin reached peak values during cardiac arrest in all patients and was significantly higher immediately after administration of the anesthetics, during cardiac arrest, and until the sixth postoperative hour in eight patients with a perioperative myocardial infarction. By contrast, the MB isoenzyme of creatine kinase reached peak values at the fourth postoperative hour and was significantly higher in patients with perioperative myocardial infarction from the fourth to the tenth postoperative hours. We conclude that myoglobin is a valuable marker of perioperative myocardial damage and is an earlier and more specific marker of perioperative myocardial infarction than creatine kinase MB.

Effect of preoperative renin-angiotensin system blockade on hypertension following coronary surgery.

Renin-angiotensin system activation is suspected of being involved in postcoronary surgery hypertension, but appears to be useful in maintaining blood pressure during anesthesia and cardiopulmonary bypass. To clarify these points, 19 patients were compared: ten as a control group and nine who received captopril during two days before surgery. Anesthesia was the same for the two groups, and cardiopulmonary bypass ensured nonpulsatile flow rates. Anesthesia induced a slight decrease in the mean arterial blood pressure of the treated group (91.1 +/- 3.3 mm Hg to 83.3 +/- 3.9 mm Hg), which did not occur in the control group (89.9 +/- 5.8 mm Hg to 89.7 +/- 4.9 mm Hg). During cardiopulmonary bypass, the mean arterial blood pressure was maintained at comparable levels in the two groups (65.6 +/- 3.5 mm Hg in the control group, 72.6 +/- 3.0 mm Hg in the treated group), with same pump flow rates. After cardiopulmonary bypass, the mean arterial blood pressure returned nearly to prebypass values. Postoperatively, three patients in the control group and four in the treated group developed hypertension. Thus, preoperative renin-angiotensin system blockade by a converting-enzyme inhibitor did not impair blood pressure regulation during anesthesia and cardiopulmonary bypass, but failed to prevent hypertension following coronary surgery.

Large encircling cryoablation without mapping for ventricular tachycardia after anterior myocardial infarction: long-term outcome.

OBJECTIVE: Map-guided procedures have been the accepted standard for ventricular tachycardia surgery. However, promising results of visually guided resections without mapping have been reported. The goal of this study was to evaluate the efficacy of large encircling cryoablation without mapping for ventricular tachycardia after anterior myocardial infarction. METHODS: Between 1985 and 1996, this procedure, along with aneurysmectomy, was performed on 38 patients for malignant ventricular tachycardia. The mean interval between the operation and myocardial infarction was 59.2 months; 7 patients (18.4%) were operated on within 1 month of myocardial infarction. The mean patient age was 62.1 +/-7.3 years and the mean left ventricular ejection fraction was 29.0% +/-7.2%. RESULTS: Hospital mortality was 2.6% (1 patient). The electrical success rate based on postoperative electrophysiologic studies was 94.5%. Overall electrical success rate was 89.1%. Freedom from ventricular tachycardia was 77% (95% CI 61%-94%) at both 5 and 7 years. Freedom from sudden cardiac death was 91% (95% CI 80%-100%) at both 5 and 7 years, with overall actuarial survivals at 5 and 7 years of 63% (95% CI 47%-80%) and 42% (95% CI 22%-63%), respectively. The main cause of late death was congestive heart failure in 62.6% of these patients. CONCLUSIONS: One can achieve good results without intraoperative mapping in the treatment of patients with ventricular tachycardia after anterior myocardial infarction by using large encircling cryoablation.

Myosin: a highly sensitive indicator of myocardial necrosis after cardiac operations.

Plasma levels of ventricular myosin fragments, determined with monoclonal antibodies to myosin heavy chains, were studied in 27 patients after cardiac operations (17 aorta-coronary bypass grafts and 10 valve replacements) to assess their possible role as a marker of perioperative myocardial necrosis. Five patients had perioperative myocardial necrosis after aorta-coronary bypass grafts as indicated by changes in the electrocardiogram and elevated levels of the MB isoenzyme of creatine kinase. Six more patients were also studied after thoracic operations performed by the same sternotomy approach. After cardiac operations, myosin levels increased from postoperative day 3 and reached peak values on day 7. Peak myosin values in patients with perioperative myocardial necrosis after aorta-coronary bypass grafting were significantly higher than in patients after an identical operation but without perioperative myocardial infarction (3793 +/- 592 versus 369 +/- 47 ng/ml; p less than 0.001). These results suggest that plasma myosin is a sensitive marker of myocardial necrosis. Furthermore, peak plasma levels of ventricular myosin after coronary bypass grafting without myocardial infarction (mean value 369 +/- 47 ng/ml) were not significantly different from peak levels after thoracic operations (mean value 253 +/- 52 ng/ml), whereas they were significantly higher after valve replacement (mean value 794 +/- 149 ng/ml; p less than 0.01). These results indicate that a certain degree of myocardial necrosis occurs during value replacement that is undetectable by the usual diagnostic criteria for perioperative myocardial infarction. We conclude that the plasma level of ventricular myosin fragments is a more specific and accurate marker of perioperative myocardial necrosis than changes in the electrocardiogram or elevated creatine kinase MB levels. Therefore the detection of myosin fragments, which appear in the serum on the third day after cardiac operations, may be useful for precise comparisons of different techniques of myocardial protection.

Prognostic value of myocardial lactate dehydrogenase subunit ratio in heart transplant recipients.

BACKGROUND: Allograft coronary artery disease (CAD) is a major long-term complication in heart transplant recipients. Unfortunately, methods for early estimation of the likelihood of development of the disease are not currently available. Lactate dehydrogenase (LDH) is composed of heart and muscle subunits. The prevalence of these subunits in LDH isoenzymes (LDH1 through LDH5) is an accurate indicator of myocardial metabolism and allows indirect estimation of oxygen availability to cardiocytes. This study investigated the prognostic value of myocardial LDH composition for the occurrence of morbid events in patients with severe allograft CAD. METHODS: Eighty-eight heart transplant recipients were followed up for a median of 4.3 years. The isoenzymes of LDH and the ratio of the heart and muscle subunits (H/M) were determined in 526 endomyocardial biopsy samples. RESULTS: Eleven patients (12%) died from allograft CAD during follow-up. They had significantly lower H/M ratios compared with event-free patients, with clear differences as early as 6 months after operation. A threshold value of 2.75 was derived from receiver operating characteristic curve analysis. Patients showing H/M values < or =2.75 had a significantly higher mortality rate than did those with higher values (p=.0003). Importantly, the H/M ratio emerged as the most powerful independent prognostic factor of death by allograft CAD (p=.001) in a multivariate model. CONCLUSIONS: Poor myocardial aerobic metabolism estimated through low H/M values was highly predictive of cardiac death resulting from severe allograft CAD. Analysis of LDH isoenzyme profile in routine endomyocardial biopsies might be of clinical value.

Aortic valve repair with fibrin glue for type A acute aortic dissection.

Repair of the acute aortic insufficiency associated with type A aortic dissection is now preferred to valve replacement. This is generally achieved by resuspending the aortic valve using different types of suturing techniques, with sutures usually passing through the aortic wall, which causes bleeding at the suture sites. We suggest, instead, simply injecting fibrin glue between the two dissected layers of the aortic annulus, which achieves resuspension of the aortic valve and reinforces the proximal stump without the need for any sutures. To evaluate the efficacy of this simple technique, the cases of 15 consecutive patients who underwent operative intervention for the treatment of the type A aortic dissection associated with acute aortic insufficiency between January 1989 and July 1993 were reviewed. The mean patient age was 63 +/- 11.2 years (range, 43 to 74 years). All had massive 3+ or 4+ aortic insufficiency, documented pre-operatively by transesophageal echocardiography. None had any history of aortic regurgitation. In all patients, the aortic repair was done in conjunction with a supracoronary replacement of the ascending aorta with a collagen-impregnated graft attached using a running suture, after reinforcement of the dissected tissues with glue. There was one non-valve-related early death (6.7%) and no late mortality. At a mean follow-up of 2.3 years, all patients were in New York Heart Association functional class I and had a mean aortic insufficiency grade of 0.3 (range, 0 to 1+). Follow-up computed tomography in all patients showed closure of the dissecting process on the proximal ascending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)

Fibrin sealant improves surgical results of type A acute aortic dissections.

From January 1984 to July 1990, 63 patients were operated on for type A acute aortic dissection. Forty-two patients (aged 22 to 80 years) had isolated replacement of the ascending aorta with the following techniques: group 1 (n = 10) had replacement of the ascending aorta with an intraluminal sutureless graft, group 2 (n = 14) had a Dacron prosthesis sutured to the aorta, and in group 3 (n = 18) the proximal and distal aortic stumps were glued together and reinforced at the suture sites with fibrin sealant before implantation of the Dacron prosthesis. There were no significant differences between the three groups with respect to age, sex, or preoperative clinical and anatomical data. Three (30%) intraoperative deaths occurred in group 1, 4 (29%) in group 2, and none in group 3. Cross-clamp and extracorporeal circulation time were significantly lower in group 1 when compared with groups 2 and 3. Perioperative blood loss during the first 24 hours was significantly lower in group 3 (372 +/- 155 mL) when compared with group 1 (755 +/- 210 mL; p less than 0.05) or group 2 (1,055 +/- 370 mL; p less than 0.01). Total hospital mortality was 7 (70%) in group 1, 6 (43%) in group 2, and 1 (5.5%) in group 3. All patients were reviewed: one late death occurred in group 2 and none in the other groups. All survivors were in good clinical condition. In conclusion, intraluminal sutureless grafts allowed shorter cross-clamp and extracorporeal circulation time but did not improve surgical results for treatment of type A acute aortic dissections.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial lactate dehydrogenase subunit ratio in cardiac allograft recipients.

BACKGROUND: Allograft coronary artery disease (CAD) is a major long-term complication in heart transplanted patients. However, the metabolic basis of allograft CAD remains to be fully elucidated. We analyzed the lactate dehydrogenase heart (H) and muscle (M) isoenzyme pattern in endomyocardial biopsy specimens and the evolution of the H/M ratio to test whether changes in this ratio could be the earliest manifestation of allograft CAD. METHODS: Twenty-four heart transplant recipients were followed up for 12 months. Endomyocardial biopsy was performed at 1, 2, 3, 6, and 12 months after transplantation. Lactate dehydrogenase 1 through 5 isoenzymes were separated by electrophoresis, and the H/M ratio was calculated. Two groups of patients were identified: group 1 (n = 20), patients without allograft CAD; and group 2 (n = 4), patients with poor outcome (three deaths, 1 case of low cardiac output) and angiographic and histologic evidence of allograft CAD. RESULTS: Both groups had similar H/M baseline values. The H/M ratio was higher (p = 0.01) in group 1 at 6 months (3.48 +/- 0.64 versus 2.17 +/- 0.43) and 12 months (3.76 +/- 0.92 versus 2.18 +/- 0.45) when compared with group 2. The H/M ratio increased from 2.78 +/- 0.89 at 1 month to 3.76 +/- 0.92 at 12 months (p = 0.02) in group 1 and decreased in group 2 (2.86 +/- 0.49 versus 2.18 +/- 0.45; not significant). CONCLUSIONS: Changes in H/M ratio reflect an anaerobic shift in the lactate dehydrogenase isoenzyme composition and can be taken as an early indicator of allograft CAD.

Use of active shunt for surgical repair of intrapericardial inferior vena caval injury.

We report a case of intrapericardial inferior vena caval disruption due to goring by a bull, and we describe the surgical repair of this uncommon penetrating cardiac injury. Review of the literature indicates that, as with other penetrating cardiac injuries, this rare lesion requires aggressive treatment involving an emergency thoracotomy. The use of an atrial caval active shunt was necessary for successful surgical management, and therefore we conclude that surgical treatment of this lesion is comparable with surgical repair of hepatic veins and retrohepatic vena caval injuries incurred during blunt vascular trauma or penetrating abdominal injuries.

Preservation of three-dimensional annular movement with the SJM-Seguin mitral annuloplasty ring.

BACKGROUND AND AIMS OF THE STUDY: In order to achieve optimal annuloplasty during mitral valve repair, we developed a new device, the SJM-Seguin annuloplasty ring, with the aim of remodeling, correcting dilatation, and preserving physiologic annulus function. This ring has variable flexibility; that is, it is sufficiently rigid in its anterior region to maintain intercommissural distance, yet sufficiently flexible in its posterior region so as not to interfere with left ventricular function and to permit the natural three-dimensional annular mobility. METHODS: Following successful studies in animals, 75 patients were operated on for mitral regurgitation between January 1994 and May 1996. The patients' mean age was 60.4 +/- 13.2 years; 53.8% were men. The cause of mitral insufficiency was degenerative in 77.4% of patients, rheumatic in 12%, ischemic in 5.3%, and infectious in 5.3%. Associated procedures were carried out in 36% of the cases. RESULTS: There were no intraoperative deaths, but two in-hospital deaths and one late death, all of which were unrelated to the annuloplasty ring. Mitral regurgitation, monitored by transesophageal echocardiography decreased from +3.42 +/- 0.6 before repair to +0.31 +/- 0.12 after repair (p < 0.005). Follow up was 100% at a mean of 14.2 months (range: 3 to 26 months). There were no annuloplasty-related complications, and especially no echocardiographically discernible systolic anterior motion. There were no transient ischemic attacks. One reoperation was performed due to endocarditis at nine months after initial repair. The average transmitral gradient was 1.94 mmHg. CONCLUSIONS: This new annuloplasty ring provides, with the absence of any valve-related complications, correction of annular dilatation and remodeling of the annulus while respecting physiologic annulus function such as natural three-dimensional mobility.

Long-term results with the Sorin Pericarbon valve in the aortic position: a multicenter study.

BACKGROUND AND AIM OF THE STUDY: A multicenter study was designed to evaluate the Pericarbon pericardial bioprosthesis for up 10 years after implantation in the aortic position. METHODS: Between January 1986 and November 1996, 321 patients (mean age 75.8 +/- 7.3 years) received 325 Pericarbon pericardial valves in the aortic position. Four patients underwent redo surgery and each received a second Pericarbon prosthesis. Associated cardiac procedures in 80 patients were mainly coronary bypass (n = 66). Follow up extended up to 10 years (cumulative follow up of 931.0 patient-years; mean follow up 3.1 +/- 2.2 years). RESULTS: There were 19 late deaths, with seven valve-related. Twelve patients suffered an embolic complication (transient cerebral attack in four, peripheral in six and induction of a myocardial infarction in two). Of these complications, five occurred within 30 days of surgery and seven beyond the first year. Ten patients were reoperated on, six for primary tissue failure, two for prosthetic endocarditis and two for paraprosthetic leak. Primary failure was due in all cases to leaflet mineralization. No primary tear of the leaflet was reported. Actuarial freedom after 10 years from primary tissue failure was 83.9 +/- 7.4% and from major embolic events 97.6 +/- 1.0%. Freedom from valve-related mortality at 10 years was 92.1 +/- 4.9%. CONCLUSIONS: These results indicate that, over a period of up to 10 years, the Pericarbon pericardial bioprosthesis compares favorably with other replacement valves.

Aspergillus flavus mitral valve endocarditis after lung abscess.

A 16-year-old male with bone marrow failure due to chemotherapy for recurrent acute lymphoblastic leukemia developed an abscess in the lower lobe of the left lung draining through a bronchogastric fistula, as well as mitral valve endocarditis with large vegetations. After a course of antifungal therapy, the left lobe was removed and the fistula closed. The mitral valve was then replaced, after a failed attempt at valve repair, by a mechanical, double-leaflet prosthesis. Microscopy of the lung and heart specimens disclosed hyphae. Cultures of both specimens on Sabouraud's medium recovered a fungus, which was identified by culturing on Czapek's medium as Aspergillus flavus. Despite further antifungal therapy, fatal embolism developed. The emboli contained the same A. flavus as the valve and lung specimens. This case confirms the grim prognosis of primary Aspergillus endocarditis in immunocompromised patients, and suggests that delayed surgical treatment and the presence of another focus of Aspergillus infection may increase the risk of death.

Malignant ventricular arrhythmias revealing anomalous origin of the left coronary artery from the pulmonary artery in two adults.

We report two cases of anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA), revealed by malignant ventricular arrhythmias in adult patients. A two coronary system was re-established in both patients, and cryotherapy was performed on one of the patients who, in addition, presented ventricular aneurysm triggering ventricular tachycardia.

Vertebral artery surgery with cardiopulmonary bypass and deep hypothermia.

Deep hypothermia was proposed to prevent neuronal ischemia and stroke during surgical procedures on arteries that supply the brain, especially with extended occlusive lesions on both internal carotid arteries. The interest of this therapeutic option is still under discussion, even in the case of combined cardiac and cerebrovascular surgery. We report the case of a 53-year-old male who was admitted to our institution for symptomatic vertebrobasilar insufficiency. Angiography showed a thrombosis of both internal carotid arteries, stenosis of both external carotid arteries, and a tight proximal stenosis of a dominant right vertebral artery. Endarterectomy and angioplasty of the origin of the right external carotid artery was done first to increase the blood supply to the brain via collateral arteries connecting the extra- and intracranial networks. Six weeks after this, a right-sided vertebral-to-carotid artery anastomosis was performed during cardiopulmonary bypass (CPB)-induced deep hypothermia for optimal neuronal protection, with good results. However, early thrombosis of the right vertebral artery requiring reintervention in normothermia, without any stroke, indicate that deep hypothermia was unnecessary in this case, probably because of the previous natural and surgical development of collateral circulation. However, there was no means of predicting this in a reliable manner before the procedure and deep hypothermia appeared a safe technique for neuronal protection without any specific postoperative complications.

Intrapericardial teratoma in infancy: a rare disease.

Intrapericardial teratoma is a rare, and generally benign, tumor originating from the 3 germinal layers. It occurs in 60% of the cases in the first two years of life. Severe cardio-respiratory distress due to mediastinal compression and pericardial effusion are the main clinical symptoms. Echo-cardiography and cine-angiography confirm the diagnosis and early surgical removal brings immediate and durable improvement.

Simple surgical technique to prevent direct secondary aortoenteric fistulas.

To prevent direct secondary aortoenteric fistulas, a devastating complication of abdominal aortic surgery, we describe here a rapid, very easy to perform and no cost operating technique. A part about 4 cm long of the vascular prosthesis was cut to obtain a partial tailored ring which was passed through the prosthesis. After the anastomosis was realized, the tailored ring was hitched up to totally cover proximal anastomosis and prevent direct contact between aorto-prosthetic anastomosis and the bowel.

Advance in mitral valve repair using a device flexible in three dimensions. The St Jude Medical-Séguin annuloplasty ring.

To allow remodeling of the annulus while respecting natural three dimensional annular movements during mitral valve repair, a new annuloplasty ring (St Jude Medical [SJM]-Séguin annuloplasty ring) was developed. This ring has variable flexibility; that is, it is sufficiently rigid on the anterior portion to maintain intercommissural distance, and sufficiently flexible on the posterior portion to respect left ventricular function and natural three dimensional annular mobility. Fifty patients operated on for pure mitral regurgitation between January, 1994 and June, 1995 were studied. Mean age was 58 years. The cause of mitral insufficiency was degenerative in 80% of the patients, rheumatic in 12%, ischemic in 4%, and infectious in 4%. The operative technique to restore normal valve coaptation was quadrangular resection in 31 cases, commissurotomy and chordal fenestration in 8, use of polytetrafluoroethylene chordae in 6, and chordal shortening or transposition in 5. Annuloplasty with a SJM-Séguin annuloplasty ring was realized in all 50 cases. Transesophageal echocardiographic mitral regurgitation decreased from 3.6 +/- 0.8 to 0.3 +/- 0.2 after repair (p < 0.005). Two post operative deaths due to non valve related complications, were observed. There were no ring related complications, especially no left ventricular outflow tract obstruction due to systolic anterior motion. Patients were all reviewed at a mean follow-up of 12.1 months (range, 9-27 months). All are well, in New York Heart Association functional Class I. Echocardiography showed a mean 0.4 +/- 0.3 mitral regurgitation, absence of any systolic anterior motion, and satisfactory mobility of the annuloplasty ring after the movements of the natural annulus, including non planar deviation. These preliminary results suggest that this annuloplasty ring 1) provides excellent correction of annular dilatation and remodeling of the annulus, 2) avoids systolic anterior motion observed with rigid rings, and 3) preserves physiologic three dimensional annulus motion.

[Results of combined valvular and coronary surgery]. / Résultats de la chirurgie combinée valvulaire et coronaire.

Between 1975 and 1984, 50 patients underwent cardiac valve replacement combined with coronary revascularization. All had heart failure (class II 28, class III 18, class IV 4), and only 39 complained of angina, including 12 who had previously experienced myocardial infarction; 32 aortic valves, 17 mitral valves and 1 mitral + 1 aortic valve were replaced, these operations being combined with 1 to 4 bypasses (mean: 1.3) per patient. The overall peri-operative mortality rate (i.e. before the 30th post-operative day) was 12 p. 100 (aortic valve 6.2 p. 100, mitral valve 23.5 p. 100), with a regular decrease since 1978. The overall incidence of peri-operative infarction was 6 p. 100 (2.4 p. 100 after 1978). After the peri-operative period 15 patients died, 8 of them of cardiac disease (6 of heart failure, 1 of myocardial infarction, 1 of embolic accident). All survivors were improved, with only 3 cases of heart failure and 1 case of residual angina during a mean follow-up period of 36.1 months (range: 6-120 months). In combined valvular and coronary surgery the mortality rate and the incidence of peri-operative infarction have gradually decreased as years went by, and they are now similar to those of valvular surgery alone. This decrease is due to the progress achieved in cardiac surgery, notably to optimal myocardial protection and maximal revascularization. This progress, together with technical improvements in anaesthesia and intensive care, has rendered combined surgery feasible with an acceptable operative risk and with such satisfactory long-term results that patients over 70 years of age can now be offered this type of treatment.