Search PubMed⌕ Search

Biomedical subjects

N A Stolf

Publications and source records attributed to N A Stolf.

At least 73 records · Page 4Linked to original sources
PubMed1992

Effects of dynamic cardiomyoplasty on regional wall motion, ejection fraction, and geometry of left ventricle.

BACKGROUND: Dynamic cardiomyoplasty may provide functional and hemodynamic improvement in patients with heart failure. The purpose of this study was to investigate the effects of cardiomyoplasty on global ejection fraction, regional wall motion, and geometry of the left ventricle. METHODS AND RESULTS: These parameters were determined in 10 patients submitted to cardiomyoplasty for treatment of refractory heart failure by left ventricular (LV) angiography. The studies were performed before and 16.5 +/- 4.8 months after cardiomyoplasty with the myostimulator turned on. They were repeated 24 +/- 1 hours with the myostimulator turned off in eight patients. LV ejection fractions were determined by the area-length method, and the centerline method was used for assessment of regional wall motion. LV geometry was studied by LV major-to-minor axis ratio and sphericity index. A LV ejection fraction improvement from 15 +/- 8% to 30.9 +/- 8.3% (p < 0.01) was demonstrated with the myostimulator turned on after cardiomyoplasty. The values with the myostimulator turned off were 23 +/- 13%, remaining higher than the values observed before surgery (p < 0.05). Regional wall motion analysis showed an improvement in all studied regions. Regarding the LV shape, the left ventricle became markedly more spheric in the diastole. CONCLUSIONS: Dynamic cardiomyoplasty may improve LV function in selected patients. The analysis of LV wall motion corroborated these results, and these changes were associated with modifications in the LV geometry.

Assisted Circulation↗
PubMed1991

Management of aortic insufficiency in chronic aortic dissection.

From January 1980 to December 1988, 44 patients with chronic aortic dissection and aortic insufficiency underwent operation. This group of patients was analyzed to evaluate the outcome of those in whom the aortic valve was preserved compared with those having valve replacement. The overall preoperative characteristics of the two groups were similar except for the incidence of Marfan's syndrome. Valve replacement was the elected procedure in patients with valve degeneration or annuloaortic ectasia. In patients with leaflet prolapse with or without an enlarged annulus, a plastic procedure was used. In 48% of the patients, it was possible to preserve the valve. There were five hospital deaths (11%): three were due to low-output syndrome, one was due to bleeding, and one was due to neurological complications. There were two late deaths (5%). Follow-up of the 37 surviving patients ranged from 2 to 108 months (mean follow-up, 18 months). Seventy-eight percent of the survivors were in functional class I and the others were in class II. Two patients in whom the aortic valve was preserved had mild aortic insufficiency. Three patients with bioprostheses underwent reoperation because of prosthetic valve dysfunction. One patient who had aortoplasty and an aortic valve plastic procedure was seen with redissection and aortic insufficiency after 60 months and was reoperated on using the Bentall technique. The actuarial survival curves showed that patients who underwent valvoplasty had higher, but not significantly higher, survival rates than the valve replacement patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Intrapericardial diaphragmatic hernia associated with atrial septal defect].

The authors report the case of a patient with atrial septal defect who was submitted to surgical treatment when an intrapericardial hernia was found. The septal defect was closed with a bovine pericardial patch and the hernia with a pediculated autogenous pericardial graft. They discuss several aspects of the classification of the hernia, its association with other anomalies, embryogenesis, pathophysiology, prognosis and surgical correction.

Child↗
PubMed1991

Survival improvement with dynamic cardiomyoplasty in patients with dilated cardiomyopathy.

Surgical support to the failing heart has been investigated in the treatment of severe myocardial failure. Dynamic cardiomyoplasty was indicated in 32 patients with dilated or chagasic cardiomyopathy who were in New York Heart Association (NYHA) class III or IV despite maximum medical therapy. Fifteen patients were operated on, and 17 refused the surgical treatment and were maintained by clinical means. With an average follow-up period of 12.3 months, actuarial survival rates for cardiomyoplasty patients were 86.6% at 6 months, 78.7% at 1 year, and 65.6% at 2 years of follow-up, whereas patients under medical therapy presented survival rates of 58.8%, 41.1%, and 27.4% at the same periods, respectively (p = 0.03). Furthermore, five of the 11 surviving patients of the cardiomyoplasty group are in NYHA class I, five in class II, and one in class III. At 6 months of cardiomyoplasty follow-up, rest radioisotopic left ventricular ejection fraction increased from 20.1 +/- 3.9% to 26.8 +/- 7.5% (p less than 0.01). Cardiopulmonary exercise testing showed that maximum oxygen consumption during treadmill testing improved from 14.7 +/- 3.9 to 18.3 +/- 3.9 ml/kg/min (p = 0.01). At 1 year of follow-up, these data remained essentially unchanged. In conclusion, dynamic cardiomyoplasty reverses congestive heart failure and improves the long-term survival of patients with severe cardiomyopathies.

Adult↗
PubMed1991

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.

Adolescent↗
PubMed1990

[Endomyocardial fibrosis. Course in patients undergoing clinical and surgical treatment].

PURPOSE: To follow-up a group of patients during a period of time after either clinical or surgical approach. PATIENTS AND METHODS: A hundred and twenty-one patients were studied retrospectively with endomyocardial fibrosis (EMF) for a period that varied from one month to 11 years (mean = 32 months). Upon entrance, patients had from 5 to 64 years of age (mean = 30), being 41 male and 80 female. Biventricular involvement were present in 70 cases, whereas 36 showed pure left and 15 pure right ventricular involvement. The patients were divided in two groups: 62 treated clinically, and 59 surgically, the latest defined as fibrosis resection added to atrioventricular valve rebuilding or replacement. All surgical cases had a prior III to IV functional class (NYHA). RESULTS: In the clinical group there were 24 fatalities, 21 who were in class IV, 1 in class III, and 2 in class II. In the surgical group there were 18 fatalities, 12 early and 6 late. CONCLUSIONS: (1) All the patients who survived the operation showed functional class improvement; (2) surgical mortality decreased in the latest years; (3) clinical treatment is indicated to patients in classes I and II, groups with low mortality rates; (4) surgical treatment is indicated to patients in classes III and IV, provided that clinical mortality is high in these groups of patients.

Adolescent↗
PubMed1990

[Results of replacement of ascending aorta, and aortic valve with reimplantation of coronary arteries].

PURPOSE: To analyse a 10-year experience with the Bentall and De Bono technique for surgical treatment of aneurysms of ascending aorta. PATIENTS AND METHODS: From January 1980 to December 1989, the Bentall and De Bono technique was employed in 38 patients. Twenty-two patients had aneurysm of ascending aorta with aortic insufficiency; 14 had chronic aortic dissections. Four patients were operated on previously by other techniques. RESULTS: The immediate mortality was 5.2%; one patient due to low-output syndrome and one had neurological complications. Five patients (13.1%) died late postoperatively. The surviving 31 patients were followed up from two to 72 months (mean 25). Of these, 29 (93.5%) were in functional class I and two in class II. Sixteen patients had late evaluation by one or more of the following methods: digital angiography, chest computerized tomography, echocardiography, or conventional angiography, 6 to 60 (mean 33) months after operation. All of them had good conditions of composite valve graft and coronary artery reattachment. The immediate and late results were similar in patients with aneurysms and aortic dissections. CONCLUSION: The aortic valve and aortic ascending portion replacement with reimplantation of coronary arteries is of low mortality and fairly good late outcome.

Actuarial Analysis↗
PubMed1990

Latissimus dorsi cardiomyoplasty in the treatment of patients with dilated cardiomyopathy.

Stimulated skeletal muscle grafts have been proposed as a means to reinforce ventricular wall in the treatment of severe myocardial failure. Latissimus dorsi cardiomyoplasty was performed in 11 patients with advanced heart failure due to cardiomyopathy who were in New York Heart Association (NYHA) class III or IV despite maximal medical therapy. There were no operative deaths. Eight patients were followed for a mean of 10.8 months. Two patients remain in muscle conditioning protocol. One patient died with latissimus dorsi ischemia and congestive heart failure. Four of the eight patients in long-term follow-up are in NYHA class I, three in class II, and one in class III. At 3 months of follow-up, rest radioisotopic left ventricular ejection fraction increased from 20.5 +/- 3.6% to 26.8 +/- 8.1% (p less than 0.01). Doppler-echocardiography demonstrated that left ventricular segmental wall shortening improved from 11.3 +/- 2.5% to 16.5 +/- 3.9% (p less than 0.01) and left ventricular stroke volume from 22.9 +/- 4.6 to 33.1 +/- 10 ml (p less than 0.01). Cardiopulmonary exercise test showed that maximal oxygen consumption during treadmill test increased from 14.8 +/- 3.7 to 18.2 +/- 3.3 ml/kg.min (p less than 0.05). At 6 months of follow-up, all the above values remained essentially unchanged. Furthermore, nonsustained ventricular tachycardia was abolished without specific medical therapy in four patients. Thus, cardiomyoplasty improves left ventricular function, reverses congestive heart failure, and may improve long-term survival in severe cardiomyopathies.

Adult↗
PubMed1990

[Spectral analysis of the arterial pulse during extracorporeal circulation. Experimental study in dogs].

PURPOSE: Spectral analysis of arterial pulse was performed during cardiopulmonary bypass with both pulsatile and continuous flow in order to evaluate the pulse model best suitable to reproduce physiological circulatory conditions. MATERIAL AND METHODS: Ten adult mongrel dogs were submitted to cardiopulmonary bypass with a roller pump for continuous flow and pulsatile flow pump in parallel. The physiological pressure waves, the roller pump waves and the pulsatile pump flow waves were recorded. During the pulsatile flow we varied the ejection period of the pump in relation to the total cycle by 70%, 60%, 50%, 40% and 30%. RESULTS: The roller pump flow showed a bifid wave followed by single peak wave. During spectral analysis we observed three harmonic components of the same amplitude. The using of the pulsatile pump flow proportioned, by spectral analysis, harmonic components whose amplitudes are inversely proportional for ejection/cycle ratio. CONCLUSION: The fundamental component of the pressure wave during the physiological flow, the pulsatile flow, and that of the roller pump stays the same, if the same blood flow is maintained; the pulse of the flow is inversely proportional to the ejection/cycle ratio; the roller pump produces a flow pattern that cannot be described as laminar; the ejection/cycle ratio of 30% seemed ideal for the performance of pulsatile flow perfusion.

Animals↗
PubMed1989

Cardiomyoplasty benefits in experimental myocardial dysfunction.

Beneficial effects of cardiomyoplasty have been documented and the use of this technique in the treatment of dilated cardiomyopathy have been suggested. This study was undertaken to evaluate the effectiveness of stimulated preconditioned latissimus dorsi muscle flaps wrapped around the heart in order to restore ventricular contractility in six adult mongrel dogs with induced myocardial dysfunction by administration of beta blockers and volume loading. Hemodynamic and two-dimensional echocardiographic evaluation were performed 1 week after the surgical procedure and immediately after heart failure induction. With synchronous pulse train electrical stimulation, cardiac output increased from 1.46 +/- 0.13 (+/- SD) to 2.01 +/- 0.16 L/min (p less than 0.01), pulmonary wedge pressure decreased from 15.5 +/- 1.2 to 11.3 +/- 1.6 mmHg (p less than 0.01) and left ventricular end-diastolic pressure from 18.3 +/- 2.4 to 13.5 +/- 1.4 mmHg (p less than 0.04). Echo derived left ventricular ejection fraction increased from 39.3 +/- 2.4 to 59.6 +/- 2.9% (p less than 0.01) and segmental wall shortening from 15.4 +/- 1.2 to 26.3 +/- 1.7% (p less than 0.01), inclusive when the muscle flap was wrapped only around the left ventricle. In conclusion, this study suggests that cardiomyoplasty may be an alternative method of treatment for irreversible cardiomyopathy, including in patients with a great cardiac enlargement in which muscle flap may only be wrapped partially around the heart.

Animals↗
PubMed1989

[Evaluation of aortic insufficiency in aortic dissection. Significance of intraoperative echocardiography on the conservation of the valve. A case report].

A 34-year old man presented with dyspnea and a new murmur of aortic regurgitation (AR). Two months before he had a episode of acute chest pain. The diagnosis of type A chronic aortic dissection was done on the basis of clinical signs and digital angiography. At surgery, intraoperative two-dimensional echocardiography (Iop Echo) showed a large intimal flap prolapsing into the leaflets during diastole causing AR, without primary involvement of the aortic valve. The aorta was transected just above the valve commissures and a 30 mm woven graft was sutured end to end. The false lumen was closed distally and incorporated into the graft-aorta suture line. Valve replacement was not performed. After the surgical procedure, a Iop Echo indicated competence of the aortic valve by means of contrast injection in the aortic root. AR due to the interference of an intimal flap with the aortic leaflets was not yet been reported. To our knowledge, this is the first case of this mechanism and illustrates the potential value of Iop Echo in diagnosis of aortic dissection.

Adult↗
PubMed1989

[Acute pulmonary edema due to dysfunction and/or rupture of the papillary muscles in patients with coronary insufficiency. Surgical results].

Acute mitral regurgitation due to severe papillary muscle dysfunction or rupture has a poor clinical outcome and often requires an emergency surgical procedure. Pulmonary venous congestion generally occurs as an end-stage event and in these patients surgery is often postponed or even not considered. We studied 14 consecutive patients with coronary artery disease that suffered acute pulmonary edema soon after mitral regurgitation was diagnosed; they were 8 (57%) male and 6 (43%) female with mean age 60-8 years (49 to 69 years). Five patients had an acute myocardial infarction and 9 had an old infarction or stable angina. Surgical treatment was indicated to all patients: mitral valve replacement or reconstructive procedure (annuloplasty) was the only procedure in 2 patients and was associated to coronary artery revascularization in the other 12. Two patients (14.3%) with acute myocardial infarction died in hospital; the remaining 12 (85.7%) had hospital discharge and did well in the late follow-up period. We concluded that this high-risk group of patients is particularly suitable for surgical management since medical treatment carries a very poor prognosis.

Acute Disease↗
PubMed1989

Determinants of survival in endomyocardial fibrosis.

This study describes the clinical course of 108 patients with endomyocardial fibrosis. There were 76 females and 32 males, with a mean age of 35 years. All patients underwent cardiac catheterization. The angiographic data show that 64 (59%) patients had biventricular involvement. From a clinical point of view, 91 (84%) were in New York Heart Association functional classes III and IV. According to the right and left ventricular intensity of fibrosis, the patients were classified as mild (40 [37%]), moderate (36 [33%]), or severe (32 [30%]) for the right ventricle and mild (19 [18%]), moderate (61 [56%]), or severe (28 [26%]) for the left ventricle. Tricuspid regurgitation was observed in 63 (58%) patients and mitral regurgitation in 65 (60%) patients. Fifty patients in functional classes III and IV underwent surgical treatment. Survival curves constructed according to functional classes showed better prognosis for those in classes I and II (p = 0.0452). Survival curves for patients in classes III and IV for clinical and surgical treatment showed a trend toward better results for the surgical group. Analysis of factors that may have influenced the course of endomyocardial fibrosis showed that biventricular involvement (moderate or severe), right ventricular fibrosis, and presence of tricuspid and mitral regurgitation were associated with greater mortality.

Adolescent↗