The Medicine, Angioplasty or Surgery Study (MASS): a prospective, randomized trial of medical therapy, balloon angioplasty or bypass surgery for single proximal left anterior descending artery stenoses.

OBJECTIVES: This study sought to evaluate, in a prospective and randomized trial, the relative efficacies of three possible therapeutic strategies for patients with a single severe proximal stenosis of the left anterior descending coronary artery and stable angina. BACKGROUND: Although percutaneous transluminal coronary angioplasty and coronary artery bypass surgery are often performed in patients with a single proximal stenosis of the left anterior descending coronary artery, it is unclear whether revascularization offers greater clinical benefit than medical therapy alone. METHODS: At a single center, 214 patients with stable angina, normal ventricular function and a proximal stenosis of the left anterior descending coronary artery > 80% were randomly assigned to undergo mammary bypass surgery (n = 70), balloon angioplasty (n = 72) or medical therapy alone (n = 72). Angioplasty had to be considered technically feasible in every case. The predefined primary study end point was the combined incidence of cardiac death, myocardial infarction or refractory angina requiring revascularization. RESULTS: At an average follow-up period of 3 years, a primary end point had occurred in only 2 patients (3%) assigned to bypass surgery compared with 17 assigned to angioplasty (24%) and 12 assigned to medical therapy (17%) (p = 0.0002, angioplasty vs. bypass surgery; p = 0.006, bypass surgery vs. medical treatment; p = 0.28, angioplasty vs. medical treatment, all by log-rank test). There was no difference in mortality or infarction rates among the groups. However, no patient allocated to bypass surgery needed revascularization, compared with eight and seven patients assigned, respectively, to coronary angioplasty and medical treatment (p = 0.019). Both revascularization techniques resulted in greater symptomatic relief and a lower incidence of ischemia on the treadmill test; however, all three strategies eventually resulted in the abolition of limiting angina. CONCLUSIONS: The more aggressive therapeutic approach with initial bypass surgery for patients with a single severe proximal stenosis of the left anterior descending coronary artery is associated with a lower incidence of medium-term adverse events than coronary angioplasty or medical treatment. However, all three strategies resulted in a similar incidence of death and infarction during an average follow-up period of 3 years. This information should be taken into consideration when physicians and patients make therapeutic choices in this setting.

Surgical treatment of endomyocardial fibrosis: a new approach.

Endomyocardial fibrosis has been treated surgically for many years. For complete removal of fibrosis from both ventricles by the classic technique, each atrioventricular (AV) valve was removed and replaced with a prosthesis. Relapse of endomyocardial fibrosis has not been observed after surgical correction. Reoperations have been carried out because of complications of valve prostheses. A new surgical technique for removal of ventricular fibrous tissue with preservation of the mitral and tricuspid valves was used in nine consecutive patients with endomyocardial fibrosis. Initial results show a reduction of pulmonary hypertension, mean right and left atrial pressures and end-diastolic pressures in both ventricles. Tricuspid annuloplasty was performed in seven patients and mitral annuloplasty in five. No valve prosthesis was used. There was no death and New York Heart Association functional class improved from class III or IV in the preoperative period to class I or II in the postoperative period. These data suggest that resection of endocardial fibrous tissue can be indicated early in the clinical course and performed with preservation of the AV valves.

Perioperative acute myocardial infarction after valve replacement.

The incidence of fatal acute myocardial infarction (AMI) after valve replacement has decreased with use of cold potassium-induced cardioplegia. Despite this method of myocardial preservation, 12 of 662 consecutive patients submitted to valve replacement had this complication. This study retrospectively analyzes, in those 12 patients, the etiologic profile of fatal perioperative AMI, together with its morphologic aspects. The clinical picture in 11 patients was a refractory low cardiac output state. In only 3 cases was AMI diagnosis confirmed during life. Six patients either had a technical complication or a coronary embolus; in these patients AMI was localized in the vascular bed of a single occluded coronary artery, and its morphologic picture resembled that of usual AMI. The 6 other patients did not have a defined cause for AMI and coronary occlusion was not present. In 4 such patients, there was massive circumferential necrosis, mainly in the subendocardium; comparatively, there was a greater prevalence of hemorrhage, contraction bands and necrosis of the layer of subendocardial cells adjacent to the left ventricular cavity. The findings for this group suggest myocardial necrosis due to cell damage during cardiopulmonary bypass; no predisposing factor for perioperative AMI was identified.

Correction of pulmonary atresia with ventricular septal defect in the absence of the pulmonary trunk and the central pulmonary arteries (so-called truncus type IV).

A child with pulmonary atresia and ventricular septal defect and no extraparenchymal pulmonary arteries had all the bronchopulmonary arterial segments connected to naturally occurring systemic-pulmonary collaterals. A three-staged surgical correction was performed. At the first and second stages, the arteries of each hilus were interconnected with synthetic arteries. At the third stage, the ventricular septal defect was closed, and continuity between the right ventricle and the bilateral pulmonary circulation was established with a valved conduit giving rise to a side arm. Postoperative evolution was good, with acceptable postrepair per right ventricular--left ventricular pressure ratio.

Reconstruction of stenotic or nonconfluent pulmonary arteries simultaneously with a Blalock-Taussig shunt.

Stenosis or discontinuity of the pulmonary arteries associated with congenital cardiac defects was repaired in 12 patients, in conjunction with the Blalock-Taussig shunt. This approach was based on the following concepts: (1) The shunted blood is more uniformly distributed to both lungs, which avoids predominance of flow to the ipsilateral lung and long-term pulmonary vascular damage; (2) because adequate blood flow is maintained, the contralateral lung growth will be near normal; (3) the possibility of future surgical correction is enhanced. The ages of the patients ranged from 2 to 24 months. Five had a primary diagnosis of tetralogy of Fallot, three had double outlet of the right ventricle, three had single ventricle, and one had a truncus type anomaly. All operations were performed without cardiopulmonary bypass. Dilation of the stenotic segment was performed in two patients, enlargement of the stenotic segment in three, and resection of the segment and end-to-end anastomosis in four. Nonconfluent pulmonary arteries were corrected in three patients. In one, the stenotic segment was resected and an anastomosis was made between the left pulmonary artery and pulmonary trunk. In another patient, a segment of the right subclavian artery was interposed between the pulmonary trunk and intrahilar left pulmonary artery. In the third patient, the right pulmonary artery was disconnected from the aorta and a tube was interposed between the right and left pulmonary arteries. There were no intraoperative or late deaths, and postoperative angiographic evaluations were satisfactory. We believe that in infants needing a Blalock-Taussig shunt the pulmonary artery anomalies, if present, should be corrected simultaneously.

Left ventricular function changes after cardiomyoplasty in patients with dilated cardiomyopathy.

Dynamic cardiomyoplasty has been reported in the treatment of severe myocardial failure. In this investigation significant improvement of left ventricular function with dynamic cardiomyoplasty was demonstrated in patients with dilated cardiomyopathy or Chagas' disease for more than 1 year of follow-up. Thirteen patients with advanced heart failure who were in New York Heart Association class III or IV were operated on. There were no operative deaths. Patients were followed up for a mean of 11.5 months, and two patients died during the late follow-up period. Five of nine patients observed long term are in New York Heart Association class I, three in class II, and one in class III. At 3 months of follow-up, Doppler echocardiography demonstrated that left ventricular segmental wall shortening increased from 11.4% +/- 2.3% to 16.4% +/- 3.9% (p less than 0.01), and left ventricular stroke volume from 23.9 +/- 5.7 to 34.4 +/- 10 ml (p less than 0.01). Radioisotopic left ventricular ejection fraction improved from 20.9% +/- 3.3% to 25.4% +/- 7.7% (p = 0.06), and its better increases occurred in patients with lesser left ventricular end-diastolic dimensions. Cardiac catheterization showed that left ventricular stroke work index increased from 14.6 +/- 3.8 to 23.7 +/- 6.7 gm.m/m2 (p less than 0.01), whereas pulmonary wedge pressure decreased from 24.8 +/- 3.7 to 17.2 +/- 5.8 mm Hg (p less than 0.01). At 6 and 12 months of follow-up, all the preceding values remained essentially unchanged. Thus cardiomyoplasty improves left ventricular function and may halt the steady evolution of severe cardiomyopathies.

Anatomic correction of transposition of the great vessels.

We present a new approach for anatomic correction of transposition of the great arteries. The two coronary arteries, with a piece of the aortic wall attached, are transposed to the posterior artery. The two aortic openings are closed with a patch. The aorta and pulmonary artery are transected, contraposed, ant then anastomosed. The interventricular septal defect is closed with a patch, through a right ventriculotomy approach, because the right ventricle is no longer part of the systemic circulation. Two patients, aged 3 months and 40 days weighing 4,200 and 3,700 grams, respectively, were operated upon with deep hypothermia and total circulatory arrest. There was good recovery from the operation, with normal cardiocirculatory conditions. Renal failure developed in the first patient, and she died on the third postoperative day. During this time the cardiocirculatory conditions were good. The second patient made an uneventful recovery. Hemodynamic studies 20 days after the operation showed complete correction of the malformation. Five and one-half months after the operation, he weighs 7,500 grams, and his development is very good. We believe that this operation will be reproducible by most cardiovascular septal defect and pulmonary hypertension.

Clinical and left ventricular function outcomes up to five years after dynamic cardiomyoplasty.

Improvement in congestive heart failure and left ventricular function after dynamic cardiomyoplasty has been reported in patients with severe cardiomyopathies, but the long-term effects of this procedure remain unclear. In this investigation 31 patients undergoing cardiomyoplasty for treatment of idiopathic dilated cardiomyopathy were annually investigated with radionuclide scintigraphy, Doppler echocardiography, and right-sided heart catheterization. They were in New York Heart Association functional class III or IV before the operation. No hospital deaths occurred, but one patient with progressive heart failure required urgent heart transplantation 42 days after cardiomyoplasty. The other patients were followed up from 6 to 70 months (mean 25.6 months) and 12 patients died at late follow-up. Actuarial survivals were 86% at 1 year, 61.4% at 2 years, and 42.5% at 3 to 5 years of follow-up. Multivariate analysis of factors influencing outcome showed that long-term survival was significantly affected by preoperative functional class and pulmonary vascular resistance. Functional class improved from 3.2 +/- 0.4 to 1.7 +/- 0.7 in the surviving patients (p < 0.01). Furthermore, left ventricular ejection fraction improved from 19.8% +/- 3% to 23.9% +/- 7.2% (p < 0.01), and significant changes in stroke index, arterial pressure, pulmonary wedge pressure, and left ventricular stroke work index were also found at 6 months of follow-up. In the late postoperative period, the left ventricular ejection fraction tended to decrease and returned to preoperative levels at 5 years, whereas hemodynamic variables did not change significantly. Thus, despite the tendency of the left ventricular ejection fraction to decrease at late follow-up, the long-term course of these patients seems to be characterized by the maintenance of hemodynamic improvement. However, long-term survival after cardiomyoplasty is limited by the severity of the patient's condition before the operation.

Inferior epigastric artery as a free graft for myocardial revascularization.

The inferior epigastric artery was used as a free graft for direct myocardial revascularization in 22 patients from October 1987 to July 1988. The artery was used either alone or along with internal mammary artery or saphenous vein grafts. The inferior epigastric artery was dissected through an infraumbilical incision without entrance into the peritoneal cavity. The results depend on the technique used for the aortoepigastric anastomosis. When a segment of saphenous vein or a patch of bovine pericardium was sutured to a large aortic orifice with the inferior epigastric artery previously anastomosed to these patches, the patency rate of the free grafts in the early postoperative period was 100%. Histologic examination showed identical structure of the inferior epigastric artery and the internal mammary artery. Application of the inferior epigastric artery is an attempt to increase the use of arterial grafts for myocardial revascularization.

Partial left ventriculectomy with mitral valve preservation in the treatment of patients with dilated cardiomyopathy.

OBJECTIVE: This study reports initial results of partial left ventriculectomy performed with preservation of the mitral valve in the treatment of 27 patients with idiopathic dilated cardiomyopathy. METHODS: Patients were in New York Heart Association class III or IV. Partial ventriculectomy was performed as an isolated procedure in four patients and associated with mitral annuloplasty in 23 patients. There were four hospital deaths (14.8%) and the remaining patients were followed for 11.2 +/- 6 months. RESULTS: Decrease of left ventricular diastolic diameter (81.8 +/- 8.7 to 68.5 +/- 7.6 mm, p < 0.001) and improvement of left ventricular wall shortening (12% +/- 3.1% to 18.1% +/- 3.9%, p < 0.001) were demonstrated by echocardiography after the operation. Left ventricular radioisotopic angiography showed reduction of diastolic volume (495 +/- 124 ml to 352 +/- 108 ml, p < 0.001) and increase of ejection fraction (17.7% +/- 4.6% to 23.7% +/- 8.8%, p < 0.001). Right-sided heart catheterization demonstrated improvement of stroke index (24.3 +/- 7.7 ml/m2 to 28.3 +/- 7.6 ml/m2, p < 0.01) and decrease of pulmonary wedge pressure (23.2 +/- 8.8 mm Hg to 17 +/- 7 mm Hg, p < 0.01). Similar results were documented at 6 and 12 months of follow-up. Functional class improved from 3.6 +/- 0.5 to 1.4 +/- 0.6 (p < 0.001). However, seven patients died at midterm follow-up because of heart failure progression or arrhythmia-related events, and survival rate was 59.2% +/- 9.4% from 6 to 24 months of follow-up. CONCLUSIONS: Partial left ventriculectomy performed with preservation of the mitral valve improves left ventricular function and congestive heart failure in patients with dilated cardiomyopathy. Nevertheless, the high incidences of heart failure progression and arrhythmia-related deaths observed after this procedure preclude its wide clinical application.

Blood cardioplegia with warm reperfusion versus intermittent aortic crossclamping in myocardial revascularization. Randomized controlled trial.

To compare the efficiency of two methods of myocardial protection--blood cardioplegia and warm reperfusion with aspartate-glutamate enrichment of the solution versus intermittent aortic crossclamping--we randomized 60 patients for coronary artery bypass grafting. Hemodynamic parameters and hospital mortality were the end points. Pathologic antecedents and preoperative clinical conditions were similar in both group I (blood cardioplegia, 30 patients) and group II (aortic crossclamping, 30 patients). An average of 2.9 grafts per patient were performed in group I and 3.1 in group II. Duration of extracorporeal circulation was 100 +/- 28 minutes in group I and 85 +/- 23 minutes in group II (p < 0.05). The total time of aortic crossclamping was 62.8 +/- 24.5 minutes in group I and 44.3 +/- 14.9 minutes in group II (p < 0.05). There were comparable increases in cardiac index in group I and group II from the preoperative period to the first postoperative day, but none of these changes reached statistical significance. There were two deaths, one in the cardioplegia group (3.3%) and another in the intermittent aortic crossclamping group (3.3%). In conclusion, in myocardial revascularization, intermittent aortic crossclamping and blood cardioplegia with warm reperfusion enriched with aspartate-glutamate solution are methods of similar efficiency.

Long-term outcome, survival analysis, and risk stratification of dynamic cardiomyoplasty.

METHODS: To analyze the long-term outcome of dynamic cardiomyoplasty, we retrospectively studied 127 consecutive patients who underwent this procedure in Paris, France (n = 76), São Paulo, Brazil (n = 37), and Portland, Oregon (n = 14). Preoperative data were collected for patients operated on between January 1985 and June 1994 and examined with respect to effect on long-term survival. Patients had a mean age of 50 +/- 13 years and were predominantly male (82%). In 46% the cause of disease was ischemic. Concomitant operations were performed in 22 patients. RESULTS: Operative mortality was 12% (15/127). Kaplan-Meier survival +/- standard error at 1 through 5 years was 73% +/- 4%, 57% +/- 5%, 49% +/- 6%, 44% +/- 6%, and 40% +/- 7%, respectively. There was a distinct improvement at 6 months in New York Heart Association functional class (3.2 +/- 0.05 vs 1.7 +/- 0.07, p < 0.0001) and a small but significant increase in left ventricular ejection fraction (20% +/- 0.8% vs 23% +/- 1.5%, p = 0.04). Ninety-day mortality was associated with low right ventricular ejection fraction, a blunted hemodynamic response to exercise testing, and requirement for an intraaortic balloon pump at the time of the operation. Using a stepwise Cox regression method of multivariable survival analysis (n = 101), we determined that atrial fibrillation, New York Heart Association class IV, high pulmonary capillary wedge pressure, and balloon pump use were independent variables simultaneously associated with poor overall survival. When metabolic testing variables were added to this model, peak oxygen consumption eliminated both pulmonary capillary wedge pressure and functional class from the model, albeit with fewer (n = 74) patients. CONCLUSION: Dynamic cardiomyoplasty is an evolving therapy for symptomatic congestive heart failure, the results of which may be enhanced by intelligent, risk-sensitive patient selection.

Low doses of inhaled nitric oxide in heart transplant recipients.

BACKGROUND: The purpose of this study was to assess the hemodynamic effects of low doses of inhaled nitric oxide in patients after orthotopic heart transplantation. METHODS: Two hours after the operation 10 adult patients who were still under anesthetic effects and undergoing mechanical ventilation inhaled, during 60 minutes, a mixture of nitrogen, oxygen, and nitric oxide (20 ppm). A standard profile of hemodynamic data was collected at baseline, at 30 minutes, at 30 more minutes of inhalation, and at the same points after nitric oxide suspension. RESULTS: A significant decrease was found from baseline to 60 minutes, immediately after nitric oxide inhalation in the following: systemic vascular resistance index 1268 +/- 409 to 1090 +/- 354 (p = 0.0161); pulmonary vascular resistance index 252 +/- 124 to 154 +/- 98 (p < 0.05); pulmonary vascular resistance index/systemic vascular resistance index ratio 0.21 +/- 0.09 to 0.14 +/- 0.08 (p = 0.0025); transpulmonary gradient 12 +/- 3 to 9 +/- 3 (p = 0.05). A significant increase was also found in cardiac index from 4.2 +/- 1.1 to 4.9 +/- 1.4 (p = 0.0007). Other parameters such as mean pulmonary, systemic, wedge and right atrial pressures, in addition to intrapulmonary shunting, heart rate, and oxygen extraction ratio, did not present any significant changes. The procedure was well tolerated by all patients, and no undesirable effects such as methemoglobin elevation or worsening of pulmonary hypertension after nitric oxide suspension were observed. CONCLUSIONS: The beneficial effects observed by inhaled nitric oxide in the pulmonary vascular resistance index/systemic vascular resistance index ratio, transpulmonary gradient, and cardiac index suggest that nitric oxide acts mainly in pulmonary territory and could be a possible pulmonary vasodilator agent used to control central hemodynamics after heart transplantation.

Quality of life after cardiomyoplasty.

Cardiomyoplasty has recently been used as a surgical treatment for refractory heart failure, but its results have not been well described in quality-of-life patterns. We studied the quality of life of 14 patients (13 men, with a mean age of 43.3 +/- 7.4 years) submitted to this procedure for treatment of dilated or ischemic cardiomyopathies. They were approached by personal, structured interviews before and 13 +/- 9 months after the procedure, focusing on the following areas: physical activity, food and sleep patterns, working status, social activity, sexual activity, psychologic state, and perceptions and expectations about the treatment. The presence of limitation descriptors (discomfort, disability, and dissatisfaction) was recorded for all patients. The results showed an important decrease in limitation of physical activity, sleep pattern, social activity, and perceptions and expectations about the treatment. These findings suggest that cardiomyoplasty may improve the quality of life of a selected group of patients.

Acute myocardial infarction with diffuse endarteritis, contraction bands, and distal thrombosis of the coronary arteries in a heart transplant patient.

The case history of a heart transplant patient who died of an acute myocardial infarction 6 months after the procedure is described. The finding of contraction bands and thrombosis associated with endarteritis suggests that coronary vasospasm may have contributed to the acute myocardial infarction during an episode of vascular rejection.

Hemodynamic effects of hypertonic sodium chloride during surgical treatment of aortic aneurysms.

Thoracoabdominal aortic surgery with aortic clamping is normally associated with major volemic shifts when the clamp is removed. This study compares the hemodynamic effects of hypertonic (HS) and isotonic (IS) solutions of sodium chloride (NaCl) infusions on the severe hypotension which follows aortic unclamping. Five consecutive patients received HS, and five received IS immediately after aortic unclamping. Blood loss, diuresis, and blood and crystalloid infusions were monitored throughout the operation. Blood gases, and pH, and hematocrit, hemoglobin, and plasma electrolyte levels were controlled during and 24 hours after surgery. Systemic arterial pressure, pulmonary arterial and wedge pressures, cardiac output, and systemic and pulmonary vascular resistance were monitored at the start of the operation, during aortic clamping, immediately after unclamping, immediately after HS or IS NaCl infusion and at the end of the operation. Patients who received HS NaCl exhibited higher pulmonary arterial and wedge pressures, higher cardiac index, and lower systemic and pulmonary vascular resistances immediately after the infusion. These patients required less volume transfusion than patients who received IS NaCl, despite slightly higher blood losses. It is concluded that HS NaCl is useful for the treatment of human hemorrhagic shock.

Dynamic cardiomyoplasty in South America.

BACKGROUND: Dynamic cardiomyoplasty has been proposed in the treatment of severe cardiomyopathies. However, few reports to date have shown significant numbers of patients collected on a multicenter basis. METHODS: From July 1987 to June 1994, dynamic cardiomyoplasty was performed in 112 patients in South America. The indications were dilated cardiomyopathy in 96 patients, Chagas' disease cardiomyopathy in 13, and ischemic cardiomyopathy in 3. Left latissimus dorsi muscle was used in all patients. RESULTS: The thirty-day mortality rate was 8.1%, and patients were followed up for 22.1 +/- 18.6 months. Data of surviving patients show that 47.3% were in New York Heart Association functional class I, 45.6% in class II, and 7% in class III or IV 1 year after the operation. The 1-year survival was 78.4%; 2-year, 59.7%; and 5-year, 41.7%. The survival at 1 year was 86.1% for patients with dilated cardiomyopathy and 40% for those with Chagas' disease. At 5 years, these values were 49.8% and 9.5%, respectively. Long-term survival was also significantly affected by preoperative functional class and pulmonary vascular resistance. However, patients operated on in class III or intermittent class IV and without elevated pulmonary vascular resistance had survival rates of 91.5% at 1 year and 76.7% at 5 years of follow-up. CONCLUSIONS: Cardiomyoplasty improves the functional status of patients with severe cardiomyopathies. Otherwise, long-term survival after this procedure is limited in patients with Chagas' disease and by patients' condition before the operation.

Transxiphoid approach without median sternotomy for the repair of atrial septal defects.

BACKGROUND: Interest in minimally invasive procedures has recently increased because it results in less surgical trauma, decreased patient discomfort, short hospital stay, reduced costs, and better cosmetic appearance. Based on these facts, we have been using the transxiphoid process approach without sternotomy for the correction of atrial septal defects. METHODS: From July 1996 to January 1997, the xiphoid process window approach was performed in 10 patients with ostium secundum atrial septal defect. Ages ranged from 6 months to 14 years (mean, 5.3 years). In all patients, extracorporeal circulation was carried out by means of cannulation of the femoral artery and both caval veins and of aortic cross-clamping. Videothoracoscopy was used to improve visualization of the aorta. RESULTS: There were no intraoperative or postoperative complications, and in all but 1 patient, extubation was possible while in the operating room. CONCLUSIONS: The xiphoid process window, with no median sternotomy, permitted closure of the atrial septal defects with good results and could be used as a less invasive technique for their correction.

Current expectations in dynamic cardiomyoplasty.

Dynamic cardiomyoplasty has been evaluated in the treatment of severe cardiomyopathies. This report outlines the results of this procedure in 21 patients with dilated or ischemic cardiomyopathy who were in New York Heart Association class III or IV before operation. There were no operative deaths. Patients were followed up for a mean of 17.6 months. Eight patients died during late follow-up, and actuarial survival rates were 73.2% at 1 year and 65.9% at 2 years of follow-up. Functional class improvement was documented in the surviving patients. Furthermore, significant improvement in left ventricular function was demonstrated by radioisotopic angiography and by heart catheterization for more than 2 years after the operation. These studies documented that left ventricular ejection fraction increased as a result of global improvement in regional wall motion. Absence of clinical and hemodynamic improvement after cardiomyoplasty seems to be related to muscle flap ischemic compromise, whereas the patient's condition before operation seems to influence the long-term outcome of cardiomyoplasty.

A new valve retractor for mitral valve procedures.

Optimal exposure greatly facilitates reconstructive mitral valve procedures. We describe an effective method for exposing this valve using a specially designed mitral valve retractor. This technique proved useful in 321 patients who underwent operation on the mitral valve.