Ventricular evoked response in patients with hypertrophic obstructive cardiomyopathy treated with DDD pacing.

OBJECTIVE: To assess the changes in ventricular evoked responses (VER) produced by the decrease in left ventricular outflow tract gradient (LVOTG) in patients with hypertrophic obstructive cardiomyopathy (HOCM) treated with dual-chamber (DDD) pacing. METHODS: A pulse generator Physios CTM (Biotronik, Germany) was implanted in 9 patients with severe drug-refractory HOCM. After implantation, the following conditions were assessed: 1) Baseline evaluation: different AV delay (ranging from 150 ms to 50 ms) were sequentially programmed during 5 to 10 minutes, and the LVOTG (as determined by Doppler echocardiography) and VER recorded; 2) standard evaluation, when the best AV delay (resulting in the lowest LVOTG) programmed at the initial evaluation was maintained so that its effect on VER and LVOTG could be assessed during each chronic pacing evaluation. RESULTS: LVOTG decreased after DDD pacing, with a mean value of 59 +/- 24 mmHg after dual chamber pacemaker, which was significantly less than the gradient before pacing (98 + 22 mmHg). An AV delay > 100 ms produced a significantly lower decrease in VER depolarization duration (VERDD) when compared to an AV delay < or = 100 ms. Linear regression analyses showed a significant correlation between the LVOTG values and the magnitude of VER (r = 0.69; p < 0.05) in the 9 studied patients. CONCLUSION: The telemetry obtained intramyocardial electrogram is a sensitive means to assess left ventricular dynamics in patients with HOCM treated with DDD pacing.

Urinary hydrocolpos, cloacal malformation and pre-axial polydactyly: a rare variant of neonatal hydrocolpos.

Hydrocolpos is characterized by a vaginal obstruction with cystic dilatation of the vagina. The latter is usually caused by accumulation of cervical and endometrial mucus but in rare instances urine is accumulated through a vesicovaginal fistula proximal to the obstruction. Hydrocolpos and hydrometrocolpos may be associated with other malformations, such as postaxial polydactyly, anal atresia, esophageal atresia, renal agenesis, genital anomalies, and cardiopathy. Each neonate presenting with hydrocolpos should be evaluated for other clinically silent malformations, such as hamartoblastoma of the hypothalamic region. We report a patient with urinary hydrocolpos and cloacal malformation; it is the first case of hydrocolpos with pre-axial polydactyly. We briefly describe embryogenesis of the different types of vaginal obstruction and discuss prenatal and neonatal diagnosis and differential diagnosis.

Inhibition of Na+/H+ exchanger attenuates neutrophil-mediated reperfusion injury.

BACKGROUND: The effect of Na+/H+ exchange inhibition in neutrophil-induced reperfusion injury was investigated using a new amiloride analogue, 5-methyl-N-isobutyl amiloride (MIA). METHODS: Rat neutrophils were separated using Percoll gradient. Luminol chemiluminescence intensity of isolated neutrophils was depressed by MIA in a dose-dependent manner. RESULTS: The effect of MIA on neutrophil-induced reperfusion injury was evaluated in Langendorff-perfused rat hearts subjected to 30 minutes of normothermic ischemia. Postischemic left ventricular developed pressure recovery was depressed by the reperfusion with neutrophils (60% +/- 7% to 33% +/- 26%) and was reverted by MIA pretreatment (86% +/- 17%, p < 0.05). MIA also improved percent recovery of coronary flow (51% +/- 2% to 70% +/- 13%), reduced creatine kinase (0.28 +/- 0.1 to 0.085 +/- 0.03 IU.L-1.g-1 dry wt), and lactate dehydrogenase leakage (10.6 +/- 3.8 to 5.16 +/- 1.3 IU.L-1.g-1 dry wt) significantly. The incidence of reperfusion-induced ventricular fibrillation also was reduced by MIA. CONCLUSIONS: The inhibition of Na+/H+ exchange shows a protective effect against neutrophil-induced reperfusion injury possibly by inhibiting the activation of neutrophils.

Late outcome of unsupported annuloplasty for rheumatic mitral regurgitation.

OBJECTIVES: The aim of this study was to evaluate medium- and long-term (range 4 months to 17 years) clinical results in a series of patients treated surgically by unsupported mitral annuloplasty. BACKGROUND: Mitral valve regurgitation has usually been treated by valve replacement or ring annuloplasty. A few series have reported plastic repair procedures without annular support or remodeling. Furthermore, in rheumatic lesions the results have been inferior to those in degenerative mitral insufficiency, and the majority of previous reports have provided information on short- or medium-term follow-up. METHODS: One hundred fifty-four patients were operated on (55 male [36%] and 99 female [64%]). The mean age +/- SD was 36 +/- 16 years (range 5 to 73). Associated lesions comprised 47 aortic and 21 tricuspid valve lesions and 2 atrial septal defects. Patients with concomitant mitral stenosis were not included. Preoperative functional class was I or II in 19% and III or IV in 81%. The cardiothoracic ratio was 0.61 +/- 0.10. All patients underwent an unsupported mitral annuloplasty procedure in which the mural portion of the annulus was reduced by applying two buttressed mattress sutures at the commissures without compromising the width of the septal leaflet. When necessary, additional chordal procedures were performed. No patients received ring or posterior annular support. RESULTS: The early mortality rate was 1.9% (three patients; one of the three died of myocardial failure and two of pulmonary thromboembolism). The late mortality rate was 5.8% (nine patients; three of the nine died of myocardial failure, one each of septicemia, pulmonary thromboembolism and sudden arrhythmic death and three of unknown causes). Twenty-eight patients (18.2%) were reoperated on because of mitral valve dysfunction and 2 (1.3%) because of prosthetic aortic valve dysfunction. A residual late systolic murmur was present in 48% of patients. Late complications were systemic thromboembolism in 5.8% (one third with an aortic valve prosthesis), infective endocarditis in 1.3% and pulmonary thromboembolism in 0.6%. Postoperative functional class was I or II in 84% and III or IV in 16%. Cardiothoracic ratio was 0.58 +/- 0.10. Actuarial probability of late survival was 79.5 +/- 5.3% at 10 years and 71.0 +/- 7.4% at 14 years. Event-free survival was 67.9 +/- 8.9% at 10 years and 56.1 +/- 11.7% at 14 years. CONCLUSIONS: Rheumatic mitral regurgitation can be effectively treated by annuloplasty without prosthetic annular support, with late results comparable to those obtained with more complicated procedures. This observation is particularly important for treatment of children and young adult patients.

A study of successful and unsuccessful low vision rehabilitation patients.

The needs of the visually handicapped are, at times neglected by our profession. This is partly due to the fact that inadequate guidelines exist to guide the occasional low vision practitioner. In an effort to shed more light on this problem, the characteristics of 84 low vision rehabilitants were studied. This group, as a whole, achieved a very high rate of success. Significant differences were found to exist between the successful and unsuccessful groups on measurements of amounts of money spent, number of devices prescribed, and best corrected visual acuity (conventional spectacles). A fourth variable, age, showed that substantial difference existed between the two groups. Possible explanations, implications, and the need for future research are discussed.