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Renato A K Kalil

Publications and source records attributed to Renato A K Kalil.

13 recordsLinked to original sources
PubMed2006

Randomized study of propofol effect on electrophysiological properties of the atrioventricular node in patients with nodal reentrant tachycardia.

BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) is probably the most common form of paroxysmal supraventricular tachycardia. Percutaneous catheter ablation is a technique to interrupt cardiac conduction pathways selectively. The anesthetist is challenged to provide a safe anesthetic which takes into account the electrophysiologist's requirements for minimal cardiac conduction interference. Propofol is an ideal drug. However, previous studies have shown that the infusion of propofol has sometimes been associated with bradyarrhythmias or conversion of arrhythmias to sinusal rhythm. The purpose of this report is to verify the interferences of propofol in the electrophysiological properties of the atrioventricular (AV) node conduction system in patients with AVNRT. METHODS: Patients were randomly assigned to receive either a placebo or propofol at sedative doses. An electrophysiological study was performed consisting of measuring the anterograde (AERPFP) and retrograde effective refractory period of the fast (RERPFP) and the anterograde effective refractory period of the slow (AERPSP) AV nodal pathway. Reciprocating tachycardia was induced and the cycle length (CL) and atrial-His (AH), His-ventricular (HV), and ventriculoatrial (VA) intervals were measured. RESULTS: Propofol did not cause alteration (P > 0.05) in the AERPFP or RERPFP and the AERPSP AV nodal pathway. The AH, HV, and VA intervals were not affected. Sustained reciprocating tachycardia could be induced in the all patients. All slow pathways were successfully identified and ablated. CONCLUSION: Propofol has no effect on the electrophysiological properties of the AV node conduction system. It is thus a suitable anesthetic agent for use in patients undergoing ablative procedures.

Adult↗
PubMed2006

Aortic valve replacement with anterior and posterior enlargement of small aortic annulus is comparable to surgery with normal annulus.

OBJECTIVE: To compare results of aortic valve replacement in patients with normal annulus and in those undergoing anterior and posterior enlargement of a small annulus to implant a larger prosthesis. METHODS: The study included 22 patients with enlargement of a small aortic annulus and 23 with a normal aortic annulus, with similar demographic characteristics and selected from a large surgical population. For normal annulus, simple valve replacement was performed. For annular enlargement, the posterior approach required incision in the mid portion of the non-coronary sinus, up to the anterior mitral leaflet; anterior enlargement was achieved by an incision between the left and right coronary ostium, extended to the ventricular septum for 2 cm. The aorta was reconstructed with bovine pericardium patches. The results analyzed included diameter of aortic annulus at surgery, clinical evolution (2 to 11 years of follow-up), left outflow tract obstruction and left ventricular mass (by Doppler echocardiography). RESULTS: Enlargement increased the aortic annulus from 18.3 +/- 2.2 mm to 24.8 +/- 2.0 mm (p < 0.001), a value similar to aortic annulus considered normal: 24.9 +/- 1.5 mm (NS). For annular enlargement, the peak systolic gradient at the prosthesis decreased from 83.6 +/- 22.3 mmHg (preoperative) to 26.7 +/- 11.4 mmHg (p < 0.01) at the last evaluation. For normal annulus, a reduction from 68.2 +/- 28.7 mmHg to 32.8 +/- 16.2 mmHg occurred (p < 0.001) (final values similar between groups; NS). Left ventricular mass at the last evaluation was 147.2 +/- 45.9 for patients with enlargement and 148.1 +/- 70.4 for those with normal annulus. CONCLUSION: Anterior and posterior aortic annulus enlargement enabled increases in annular diameter and valve prosthesis size, providing clinical and echocardiographic results similar to patients with valve replacement in a normal annulus.

Adult↗
PubMed2005

[Coarctation of the aorta in infants under one year of age. An analysis of 20 years of experience].

OBJECTIVE: A review of experience with techniques of correction used, in the last 20 years, in children younger than one year old. METHODS: In the period from 1978 to 1998, 148 patients (pt) with coarctation of the aorta (CoAo), under one year of age, with or without associated intracardiac defects, were submitted to surgery. Median age 50 days, 92 female pt (62.1%). The average weight was 4,367 +/- 1,897 gr. The average follow-up was 1,152 +/- 1,462 days. The population was divided in 3 groups: Group I, isolated CoAo: 74 pt (50%); Group II, CoAo and interventricular communication (IVC): 41 pt (27.7%) and Group III, CoAo with complex intracardiac malformations: 33 pt (22.3%). RESULTS: The total mortality was of 43 patients (29%). In patients younger than 30 days, the mortality was 53%, p=0.009, DR=4.5, between 31 and 90 days, 14.7%, p=0.69, and over 91 days, 15%, p=0.004. The probability of actuarial survival of the whole population was 67% at 5 and 10 years. Thirty-six patients (24.3%) had recoarctation, from which 18 patients (50%) were younger than 30 days, DR=6.35. The incidence of recoarctation was with Waldhausen technique in 4 patients (10%) and with the classic termino-terminal technique in 19 patients (26%) p=0.03, and isthmusplastic operation in 6 patients (37.5%). The patients younger than 30 days showed a relative risk for recoarctation de DR=6.35. The probability of actuarial survival, free of coarctation repair, at 5 and 10 years was of 69% with Waldhausen's technique and 63% with the classic termino-terminal technique. CONCLUSION: Patients younger than 30 days showed increased mortality and recoarctation risk. Waldhausen's technique in patients older than 30 days showed effective. The classic termino-terminal technique did not show to be a good option in all age ranges, being imperative to carry out more radical technical variations, such as the extended termino-terminal.

Aortic Coarctation↗
PubMed2004

Randomized study of surgery for patients with permanent atrial fibrillation as a result of mitral valve disease.

BACKGROUND: The Cox Maze procedure has been used to treat atrial fibrillation in patients with mitral valve disease. Recently, ectopic foci, originating in the pulmonary veins, were demonstrated in patients with atrial fibrillation, and the indication was that their arrhythmia could have a focal origin. In the light of this new evidence, a simplified surgical technique to isolate the pulmonary veins was developed to eliminate permanent atrial fibrillation in patients undergoing mitral valve surgery. This study compares three surgical procedures proposed to maintain sinus rhythm after mitral valve surgery. METHODS: A prospective clinical trial of 30 patients with mitral valve disease and permanent atrial fibrillation who had undergone mitral valve surgery were randomized in accordance with the type of surgery used on each: (1). associated en bloc isolation of pulmonary veins, (2). the Maze procedure, or (3). mitral valve correction alone. The preoperative clinical characteristics were similar in the three groups. RESULTS: The overall postoperative complications were similar in all three groups. The cardiopulmonary bypass time and the aortic cross-clamping time were shorter in the control group, but this factor bore no relation to increased morbidity in the intervention groups. The relative risk of atrial fibrillation after surgery was 0.08 in the group undergoing isolation of pulmonary veins (p = 0.010; 95% confidence interval, 0.01 to 0.71) and 0.20 in the Maze group (p = 0.044; 95% confidence interval, 0.04 to 1.02) compared with the control group. CONCLUSIONS: En bloc isolation of pulmonary veins associated with mitral valve surgery appears to be safe and just as effective as the Maze procedure in maintaining sinus rhythm in patients with permanent atrial fibrillation.

Atrial Fibrillation↗
PubMed2004

Isolation of the pulmonary veins in patients with permanent atrial fibrillation secondary to mitral valve disease.

OBJECTIVE: To assess the efficacy of surgical isolation of the pulmonary veins for re-establishing sinus rhythm in patients with atrial fibrillation secondary to mitral valve disease. METHODS: Thirty-three (67% were women) patients with permanent atrial fibrillation and indication for surgical correction of the mitral valve underwent surgical isolation of the pulmonary veins. Their mean age was 56.3+/-10 years, preoperative NYHA functional class was 3.2+/-0.6, left atrial size was 5.5+/-0.9 cm, and ejection fraction was 61.3+/-13%. The surgical technique consisted of a circumferential incision surrounding the 4 pulmonary veins, excision of the left atrial appendage, and a perpendicular incision originating in the inferior margin of the circumferential incision isolating the pulmonary veins down to the mitral valve. Early arrhythmias were aggressively treated with cardioversion. RESULTS: The mean follow-up was 23.9+/-17 months, and 3 patients died in the postoperative period. Ten patients required electrical cardioversion in the postoperative period; 87% had sinus rhythm in the last medical visit, and 33% were using amiodarone. CONCLUSION: Isolation of the pulmonary veins associated with mitral valve surgery is an effective and safe technique for maintaining sinus rhythm in patients with permanent atrial fibrillation.

Adult↗
PubMed2003

Right ventricular bronchogenic cyst.

We report an exceedingly rare case of primary bronchogenic cyst in the outflow tract of the right ventricle in a 48-year-old woman. In our review of the world literature, we found only 1 other report of an intracardiac bronchogenic cyst. Our patient's only symptom was mild dyspnea not associated with physical exertion, and the cyst was resected successfully. We report clinical aspects of the case, diagnostic methods, surgical management, and histopathologic findings.

Bronchogenic Cyst↗
PubMed2002

Experimental model of gene transfection in healthy canine myocardium: perspectives of gene therapy for ischemic heart disease.

OBJECTIVE: To assess the transfection of the gene that encodes green fluorescent protein (GFP) through direct intramyocardial injection. METHODS: The pREGFP plasmid vector was used. The EGFP gene was inserted downstream from the constitutive promoter of the Rous sarcoma virus. Five male dogs were used (mean weight 13.5 kg), in which 0.5 mL of saline solution (n=1) or 0.5 mL of plasmid solution containing 0.5 micro g of pREGFP/dog (n=4) were injected into the myocardium of the left ventricular lateral wall. The dogs were euthanized 1 week later, and cardiac biopsies were obtained. RESULTS: Fluorescence microscopy showed differences between the cells transfected and not transfected with pREGFP plasmid. Mild fluorescence was observed in the cardiac fibers that received saline solution; however, the myocardial cells transfected with pREGFP had overt EGFP expression. CONCLUSION: Transfection with the EGFP gene in healthy canine myocardium was effective. The reproduction of this efficacy using vascular endothelial growth factor (VEGF) instead of EGFP aims at developing gene therapy for ischemic heart disease.

Animals↗
PubMed2002

Simple surgical isolation of pulmonary veins for treating secondary atrial fibrillation in mitral valve disease.

BACKGROUND: Chronic atrial fibrillation (AF) due to mitral valve disease has been successfully treated by surgery. We performed a study to evaluate the effectiveness of a surgical method of simple pulmonary vein isolation (PVI) without radiofrequency or cryoablation in the restoration of sinus rhythm in a group of patients. METHODS: Fifteen patients were operated on for mitral valve disease and chronic AF. The technique consists basically of a circumferential incision excluding the pulmonary vein ostia from the left atrium. RESULTS: Sinus rhythm was achieved in 92.3% of the patients at 6-month follow-up. Echocardiograms 2 months after surgery showed a mean decrease of 1.1 cm in left atrial size. Effective atrial ejection was reestablished in all patients in whom sinus rhythm was achieved (mean LA ejection fraction 41% +/- 14%). Twenty-four hour Holter recordings did not show episodes of paroxysmal atrial fibrillation in any patients. Four patients had isolated episodes of ventricular ectopic beats. Stress electrocardiograms showed mean maximal ventricular response was 64% +/- 11% and 73% +/- 9% of predicted value at 2 and 6 months, respectively. All patients had improved NYHA functional class after surgery; 74% of patients were in NYHA functional class I at 6 months compared with 13.3% preoperatively. CONCLUSIONS: Pulmonary vein isolation without the use of radiofrequency or cryoablation is effective in restoring sinus rhythm in patients with chronic AF secondary to mitral valve disease. Based on simple surgical incisions, this technique is more advantageous than others requiring additional instrumentation.

Adult↗
PubMed2002

Assessment of thromboembolism after the Cox-Maze procedure for chronic atrial fibrillation secondary to mitral valve lesion.

OBJECTIVE: To assess the occurrence of late thromboembolism after surgical repair of chronic atrial fibrillation (AF) simultaneously with repair of mitral valve using the Cox-Maze procedure. METHODS: 69 patients underwent Cox 3 procedure, with no cryoablation simultaneously with mitral valvuloplasty or prosthesis. Mean age was 49.9+/-13.2 years. Mean follow-up was of 31.7+/-19 months. Types of lesion were as follows: 33 (48%) stenoses, 23 (33%) insufficiencies, and 13 (19%) double lesions. Procedures were: 64 (93%) valvuloplasties, 3 (4%) biological and 2 (3%) mechanical prosthesis placement. There were 9 (13%) patients with previous systemic embolism and 2 (3%) had left atrial thrombi. RESULTS: Early mortality was 7% and late 1%. 2 patients (3%) were reoperated for mitral placement. At last evaluation, 10 patients (15%), were in AF. The remaining 59 (85%) were either in sinus / atrial rythm (74%) or under pacing (12%). There were no occurrence of early or late, systemic or pulmonary embolism. Permanent anticoagulation was employed in 16 cases, 10 in regular rythm and 6 in AF. The remaining 47 (75%), 2 in AF and 45 in regular rythm, did not receive anticoagulants. CONCLUSIONS: These results are in accordance with others series, where the occurrence of embolism was rare after maze procedure. Permanent systemic anticoagulation seems to be unnecessary in those cases.

Adult↗
PubMed2002

Late clinical outcomes of the fontan operation in patients with tricuspid atresia.

OBJECTIVE: Evaluation of the long-term clinical results of the Fontan operation in patients with tricuspid atresia. METHODS: A retrospective analysis was made at the Instituto de Cardiologia do Rio Grande do Sul (Institute of Cardiology of Rio Grande do Sul), from August 1980 through January 2000, of 25 patients with a long-term follow-up, out of a series of 36 patients who underwent the Fontan operation or one of its variants due to tricuspid atresia. Their mean age at surgery was 5.4+/-3.1 years, and their mean weight was 15.8+/-6.1 kg, the majority of them (63.9%) being males. Four patients underwent the classical Fontan operation, 12 the Kreutzer variant, 6 the Björk variant, 9 total cavopulmonary shunt with a fenestrated tube, and 5 total cavopulmonary shunt with a nonfenestrated tube. RESULTS: The patients were followed-up on an outpatient basis, with a mean long-term survival time of 5.5+/-4.2 years (50 days to 17.8 years) and a late mortality rate of 8%. Arterial saturation increased from 77.2+/-18.8% in the preoperative period to 91+/-6.7% upon the last outpatient visit (p>0.05). At the final check, most (67%) patients were asymptomatic and 87% could tolerate exercise. Ten (40%) patients experienced some kind of complication during the long-term follow-up, such as cardiac arrhythmia, cyanosis, protein-losing enteropathy, neurological events, right heart failure, intolerance to exercise and reoperation. CONCLUSION: The results indicate that, once the immediate postoperative period is over, during which the adaptations to the new circulatory physiology occur, the evolution of patients with tricuspid atresia who underwent the Fontan operation is satisfactory, in spite of a low, yet significant, morbidity.

Adolescent↗
PubMed2002

Late results of endoventricular patch plasty repair in akinetic and dyskinetic areas after acute myocardial infarction.

OBJECTIVE: To assess the surgical results of endoventricular patch plasty repair in akinetic and dyskinetic left ventricular areas. METHODS: We studied 52 patients who had undergone endoventricular patch plasty repair associated with myocardial revascularization. The preoperative functional class distribution was as follows: class I in 1 (1.9%) patient; class II in 2 (3.8%) patients; class III in 23 (44.2%) patients; and class IV in 26 (50%) patients. RESULTS: The immediate mortality rate was 7.6% (4 patients). The clinical outcome of 44 patients followed up within a mean postoperative time of 29+/-25 months was as follows: class I in 33 (75%) patients; class II in 7 (15.9%) patients; class III in 2 (4.5%) patients; and class IV in 2 (4.5%) patients. Comparison between pre- and postoperative catheterization in 21 patients showed that the ejection fraction increased from 46.3% to 51.3% (p=0.17); the left ventricular systolic volume decreased from 76.4 mL to 57.5 mL, (p=0.078); and the left ventricular diastolic volume decreased from 141.2 mL to 105.8 mL (p=0.0 73). These findings showed the tendency toward improvement, but with nonsignificant results. CONCLUSION: The technique proved to be effective, to have a low mortality rate, to cause significant clinical improvement, an increase in ejection fraction, and a reduction in left ventricular volumes.

Adult↗