Balloon coarctation angioplasty: follow-up of 103 patients.

OBJECTIVE: To evaluate the role of balloon coarctation angioplasty (BCA) in the management of patients with native coarctation of the aorta. BACKGROUND: BCA has emerged as an alternative to surgery for patients with native coarctation of the aorta. However, its role remains controversial. METHODS: Over a 7-year period, 103 patients undergoing BCA were enrolled in the study. Hemodynamic evaluation was obtained at baseline and immediately following BCA; 75% of patients returned for follow-up evaluation at 26 +/- 20 months. RESULTS: The systolic gradient across the coarcted segment decreased from 59 +/- 18 mmHg to 10 +/- 11 mmHg following BCA (p < 0.001). The procedure was successful in 82% of patients, and partial improvement was obtained in 17%. Repeat intervention was performed in 13% of the follow-up group. Surgical intervention was needed in 8 patients. CONCLUSION: Balloon angioplasty is an effective first-line intervention in patients with native coarctation of the aorta.

Hypertension and renal injury in experimental polycystic kidney disease.

UNLABELLED: Hypertension and renal injury in experimental polycystic kidney disease. BACKGROUND: Hypertension accelerates renal failure in autosomal dominant polycystic kidney disease (ADPKD), and evidence suggests a role for the renin-angiotensin system (RAS) in the functional and structural changes. To explore the hypothesis that RAS adaptations contribute to disease progression, we examined RAS activity and the long-term consequences of antihypertensive drugs, which suppress (enalapril) or stimulate (hydralazine) the RAS, in experimental polycystic kidney disease. METHODS: Studies were conducted in male heterozygous cystic Han:SPRD rats (Cy/+) and in unaffected littermates (controls). In protocol 1, either angiotensin II (Ang II), enalaprilat, or saline vehicle was acutely infused into cystic and control rats, which were aged 10 to 12 weeks. The mean arterial pressure (MAP), glomerular filtration rate (GFR), and renal plasma flow (RPF) were measured at baseline and after an infusion of test substances. In protocol 2, cystic rats received chronic therapy with either enalapril, hydralazine, or no therapy for 10 to 12 weeks of age and then underwent renal function and RAS studies. In protocol 3, similar cohorts were followed for 40 weeks to assess the effects of therapy on blood pressure, proteinuria, serum creatinine, RAS parameters, and renal morphology. RESULTS: In protocol 1, cystic rats had massive kidneys, slightly elevated blood pressure, and profound renal vasoconstriction and reduced GFR. Ang II induced similar changes in MAP and renal function in control and cystic rats. Enalaprilat induced little effect on MAP but more striking increases in GFR and RPF in cystic rats. In protocol 2, at 10 weeks of age, enalapril was superior in preserving renal function, but neither drug limited the expansion of the tubulointerstitium. In protocol 3, at 40 weeks of age, both drugs ameliorated the increase in serum creatinine, although only enalapril reduced proteinuria and kidney size. CONCLUSIONS: In polycystic rats, acute RAS suppression markedly ameliorates renal dysfunction. However, although chronic enalapril and hydralazine protect against the loss of renal function, only enalapril limits renal growth and proteinuria, and neither significantly limits tubulointerstitial fibrosis. The long-term studies give clear support to the importance of blood pressure control, per se, but only partial support to the importance of the particular agent used. As in clinical studies, angiotensin-converting enzyme inhibition may be less beneficial in ADPKD than in renal diseases characterized by predominant glomerular injury.

Electrophysiologic effects of adenosine in patients with supraventricular tachycardia.

BACKGROUND: We correlated the electrophysiologic (EP) effects of adenosine with tachycardia mechanisms in patients with supraventricular tachycardias (SVT). METHODS AND RESULTS: Adenosine was administered to 229 patients with SVTs during EP study: atrioventricular (AV) reentry (AVRT; n=59), typical atrioventricular node reentry (AVNRT; n=82), atypical AVNRT (n=13), permanent junctional reciprocating tachycardia (PJRT; n=12), atrial tachycardia (AT; n=53), and inappropriate sinus tachycardia (IST; n=10). There was no difference in incidence of tachycardia termination at the AV node in AVRT (85%) versus AVNRT (86%) after adenosine, but patients with AVRT showed increases in the ventriculoatrial (VA) intervals (13%) compared with typical AVNRT (0%), P<0.005. Changes in atrial, AV, or VA intervals after adenosine did not predict the mode of termination of long R-P tachycardias. For patients with AT, there was no correlation with location of the atrial focus and adenosine response. AV block after adenosine was only observed in AT patients (27%) or IST (30%). Patients with IST showed atrial cycle length increases after adenosine (P<0.05) with little change in activation sequence. The incidence of atrial fibrillation after adenosine was higher for those with AVRT (15%) compared with typical AVNRT (0%) P<0.001, or atypical AVNRT (0%) but similar to those with AT (11%) and PJRT (17%). CONCLUSIONS: The EP response to adenosine proved of limited value to identify the location of AT or SVT mechanisms. Features favoring AT were the presence of AV block or marked shortening of atrial cycle length before tachycardia suppression. Atrial fibrillation was more common after adenosine in patients with AVRT, PJRT, or AT. Patients with IST showed increases in cycle length with little change in atrial activation sequence after adenosine.

Acquired cystic disease of kidney in chronic renal failure in jordan.

Acquired cystic disease of the Kidney (ACDK) is a well documented complication of end stage renal failure in patients managed conservatively or supported by dialysis. The aim of the present study is to highlight the scope of the problem among our patients, and to evaluate the clinical characteristics of the disease. A Total of 124 patients with chronic renal failure (106 on dialysis, 18 non-dialyzed) were studied with ultrasonography by the same radiologist. ACDK was defined as the presence of four or more cysts in each kidney. The cysts should have sharp smooth wall with acoustic enhancement. In non-dialyzed patients, 5.5% had ACDK, 33.5% had one to three cysts and 61% had no cysts. Among dialysis patients 42.5% had ACDK, 26% had one to three cysts and 31.1% had no cysts. During of dialysis therapy and age were greater in patients with ACDK (74 +/- 30 months. 58 +/- 3 years respectively) compared to those with no cysts (11 +/- 8 months. 26 +/- 4 years). The major clinical complications were intracystic hemorrhage in three cases and stones in seven cases. No correlation was noted between the presence of cysts and the original kidney disease, gender, hematocrit or adequacy of dialysis. We conclude that, ACDK occurs commonly in patients with chronic renal failure; however, patients are generally older and have been on dialysis longer than patients without cysts. Ultrasound, in the hands of an experienced radiologist, is a relatively adequate screening tool for ACDK and its complications.

Hospital acquired acute renal failure.

This study was performed to evaluate hospital-acquired renal insufficiency with special reference to the causative factors, clinical course and patient management. A total of 100 patients who were admitted to medical and surgical wards at the King Hussein Medical Center, Amman, Jordan over a 15-month period and who developed renal failure during their hospital stay, were referred to, and seen at the nephrology department. The patients ages varied from 18 to 77 years; there were 59 males and 41 females. Reduced renal perfusion, major surgery and administration of nephrotoxic drugs accounted for the majority of episodes of renal failure (77%). In general, non-oliguric patients fared better, they required dialysis less frequently and had lower mortality compared to the oliguric patients. Severity of renal failure and multi-organ involvement adversely affected the prognosis. However, age of the patient had no influence on the outcome.