The renal response to neuroendocrine inhibition in chronic heart failure: double-blind comparison of captopril and prazosin

Activation of the renin–angiotensin and sympathetic systemsin chronic heart failure causes important renal vasoconstriction.In a double-blind cross-over study, treatment with captoprilfor one month reduced systemic and renal vascular resistanceby 14% and 25%, increased renal blood flow by 12%, and increasedthe percentage of the cardiac output perfusion to the kidneyby 13%. Treatment with prazosin for one month also reduced systemicvascular resistance by 8%, renal vascular resistance increasedby 20%, and renal blood flow and the percentage of the cardiacoutput going to the kidney fell by 14% and 26%. During captopriltreatment, plasma aldosterone concentration was reduced to normal,but during prazosin treatment there was an initial increasein aldosterone of 45%, and a sustained increase in plasma noradrenalineconcentration of 26%. Body weight decreased by 1.7kg on captopril,but increased by 3.0 kg on prazosin, correlating inversely withthe changes in renal blood flow. Sympathetic inhibition withprazosin causes systemic vasodilatation which diverts bloodfrom the kidney and may result in fluid retention. Inhibitionof the renin system with captopril causes preferential renalvasodilatation and can improve renal perfusion in chronic heartfailure.     

Malignant melanoma: aetiological importance of individual pigmentation and sun exposure

A case-control study of cutaneous malignant melanoma (CMM) was based on 523 incident cases and 505 age- and sex-matched controls selected from the general population. The purpose was to investigate the relative risk of developing CMM associated with different sun habits and indicators of pigmentation, such as skin type, eye colour and hair colour. Compared to people with black hair, blonde subjects had a relative risk of 744 (95% confidence interval, 45.8–120.8). Associations with skin type and eye colour were considerably weaker. Relative risks of about 1.5–2.5 were found for certain sun habits. The results suggest that in a population of Caucasian origin with a predominantly fair complexion, pigmentary status characterized by hair colour is a far more important aetiological factor than sun habits.     

Ventricular septal rupture complicating myocardial infarction: is earlier surgery justified?

Fifty-five consecutive cases of ventricular septal rupture followingmyocardial infarction were reviewed in order to ascertain clinicaland haemodynamic determinants of in-hospital mortality. Factorsassociated with poor prognosis included clinical evidence ofa poor haemodynamic state or biochemical evidence of impairedrenal function.Twenty-six patients managed before 1982 (group1) were then compared with 29 managed subsequently (group 2)when a policy of earlier surgical intervention had been adopted.Patients in group 2 were more haemodynamically compromized andhad greater impairment of renal function. The surgical mortalityin group 1 was 3 of 18 patients (17%) which was not significantlydifferent from that in group 2 (7 of 22 patients, 32%).Earliersurgical intervention in ventricular septal rupture is frequentlyundertaken in critically ill patients whose prognosis is poor.However their surgical risk is not significantly increased andsuch an approach can therefore be justified as it may salvagesome patients who otherwise would not survive.     

Solitary tumour metastasis: a rare cause of right ventricular outflow tract obstruction and sudden death

The clinical features of a patient presenting with recent breathlessnessindicated right ventricular outflow tract obstruction, whileechocardiography suggested the presence of tumour in the rightventricle. Before further investigations could be instituted,she died suddenly. Autopsy revealed a haemopericardium secondaryto rupture of the right atrium while the right ventricle wasfound to contain a tumour arising from most of its endocardialsurface. Histology showed this to be a poorly differentiatedmucous secreting carcinoma similar in appearance to her coloniccarcinoma excised 8 years previously. There was no other evidenceof metastatic disease.     

Intravenous digital subtraction angiography in the diagnosis and management of acute aortic dissection

Eleven patients presenting with the clinical diagnosis of suspectedaortic dissection underwent intravenous digital subtractionaortography. In nine patients digital subtraction angiography(DSA) was performed as the investigation of first choice. Infive of these the diagnosis was confirmed with this techniquealone and surgical repair was undertaken without further investigation.Direct cine aortography was also undertaken in the other fourpatients and confirmed the DSA findings, demonstrating aorticdissection in one case and no dissection in three others. In two of the eleven patients, direct cine aortography was performedas the initial investigation. The results of subsequent digitalaortography concurred in both cases, aortic dissection beingdemonstrated in one patient. In two cases, despite normal cineand digital aortography, aortic dissection was confirmed bycomputed tomography. We have found DSA to be a valuable technique for diagnosingaortic dissection, with no false positive or false negativefindings when compared to direct cine aortography. Since itis a less traumatic procedure than direct aortography it shouldbe the investigation of choice if computed tomography is notimmediately available.     

Coronary angioplasty in cardiac transplant recipients

Accelerated coronary artery disease following cardiac transplantationremains an important obstacle to long-term survival and thecorrect management strategy remains unclear. This observational,prospective study was designed to examine the feasibility ofusing percutaneous transluminal coronary angioplasty (PTCA)in the treatment of post-transplant coronary disease. Thirteen consecutive patients were selected from the total populationof 276 transplant recipients who underwent routine coronaryangiography between 1987 and 1990. Selection of patients wason angiographic criteria alone and PTCA was performed to allaccessible stenoses with more than 80% luminal narrowing. PTCAwas performed using standard angioplasty equipment and procedureas considered appropriate for the individual lesion. A successfulPTCA was defined as more than 30% reduction in luminal narrowingand a residual narrowing of less than 50%. Restenosis was definedas a loss of 50% or more of the gain achieved at the time ofsuccessful PTCA or more than a 30% increase in narrowing atthe site of stenosis. A total of 31 lesions were dilated inthis group and a successful result was achieved in 29 of these(93%) and in 12 of the 13 patients. The one patient with failedPTCA underwent later successful coronary artery bypass graftingto complete revascularization. Four of the 13 patients havehad two angioplasty procedures, two for restenosis and two fordisease progression in other sites. One patient died 15 monthsafter the initial PTCA and remaining 12 were asymptomatic withgood exercise tolerance and ventricular function at a mean of19 months (range 1–39 months) following first PTCA. Thus, PTCA can be considered a feasible form of treatment forsignificant single and multiple vessel disease in selected cardiactransplant recipients. Further study is required to assess theeffect of this early intervention on long-term mortality.     

Ventricular septal rupture complicating myocardial infarction: is earlier surgery justified?

Fifty-five consecutive cases of ventricular septal rupture followingmyocardial infarction were reviewed in order to ascertain clinicaland haemodynamic determinants of in-hospital mortality. Factorsassociated with poor prognosis included clinical evidence ofa poor haemodynamic state or biochemical evidence of impairedrenal function.Twenty-six patients managed before 1982 (group1) were then compared with 29 managed subsequently (group 2)when a policy of earlier surgical intervention had been adopted.Patients in group 2 were more haemodynamically compromized andhad greater impairment of renal function. The surgical mortalityin group 1 was 3 of 18 patients (17%) which was not significantlydifferent from that in group 2 (7 of 22 patients, 32%).Earliersurgical intervention in ventricular septal rupture is frequentlyundertaken in critically ill patients whose prognosis is poor.However their surgical risk is not significantly increased andsuch an approach can therefore be justified as it may salvagesome patients who otherwise would not survive.