Successful surgical repair of aortic dissection presenting with complete heart block.

Acute dissection of the ascending aorta can present with complete heart block if the dissecting hematoma involves the interatrial septum near the atrioventricular node. We report a case of acute type A dissection presenting with complete heart block treated with emergency grafting of the ascending aorta, aortic valve replacement, and coronary artery bypass grafting. The patient survived, although complete heart block persisted requiring permanent pacemaker implantation.

Triple-drug immunosuppression with steroid discontinuation by six months after heart transplantation.

BACKGROUND: Triple-drug immunosuppression with cyclosporine, azathioprine, and prednisone is associated with complications which might be reduced by steroid withdrawal. METHODS: In two groups of heart transplant recipients maintained on an identical regimen of cyclosporine and azathioprine, prednisone was withdrawn in group I patients (n = 35) by 6 months after transplantation, whereas in group II patients (n = 49) prednisone was never discontinued. RESULTS: Survival was similar in the two groups. The incidence of acute graft rejection was significantly higher in group I (54%) than in group II (12%), whereas infective complications were significantly lower in group I than in group II (0.63 versus 1.02 episode/patient). The degree of posttransplantation weight gain, lipid abnormalities, and incidence of hypertension were not modified by the fast tapering of prednisone, whereas the incidence of cataract and compression fracture and the degree of bone loss were significantly reduced in group I. Graft function and incidence of coronary artery disease were similar in the two groups. CONCLUSIONS: The present data suggest that prednisone can be safely withdrawn in heart transplant recipients without jeopardizing survival and graft function. Longer follow-up is needed to assess the full impact of early withdrawal of steroids from triple-drug immunosuppression, especially on long-term graft function and incidence of coronary artery disease. Benefits of early steroid withdrawal included a reduction in bone loss, which might ultimately have a major positive impact on the extent of long-term rehabilitation and exercise tolerance after heart transplantation.

Differential reflex control of forearm and calf resistance vessels by chemosensitive cardiac afferent activation.

The aim of this study was to determine whether chemosensitive ventricular afferent activation in humans evokes a diffuse pattern of reflex vasodilation involving the skeletal muscle circulation of all the extremities or a highly specified pattern of vasodilation that is limited to the rather small vascular bed of the forearm. In 10 patients with innervated ventricles and 7 patients with denervated ventricles resulting from heart transplantation, we performed simultaneous plethysmographic recordings of blood flow in the forearm and calf during chemosensitive ventricular afferent activation with intracoronary Renografin. In patients with innervated ventricles, intracoronary Renografin evoked directionally opposite vascular responses in the forearm and calf: forearm resistance decreased from 50 +/- 11 to 31 +/- 8 units, whereas calf resistance increased from 42 +/- 7 to 59 +/- 9 units (P < 0.05, calf vs. forearm). Forearm vasodilation was eliminated after heart transplantation, indicating that this is a reflex response caused by ventricular afferents. In contrast, calf vasoconstriction was well preserved despite ventricular deafferentation, indicating that this response is caused by mechanisms other than ventricular afferent activation, possibly the sinoaortic baroreceptors. Taken together, these findings document a remarkable degree of specificity in the effects of cardiac afferent activation on the reflex regulation of regional vasomotor tone in humans.

Acute infective endocarditis.

Acute infective endocarditis is an important cardiovascular emergency that can be detected with improved diagnostic techniques. In the last few decades we have witnessed a changing spectrum of microorganisms causing infective endocarditis. Successful treatment of infective endocarditis is enhanced by the combined and cooperative efforts of the internist and the surgeon. In this article, we have discussed the clinical evaluation, laboratory techniques, and noninvasive studies by which proper diagnosis can be made and appropriate antimicrobial therapy instituted. We have also reviewed the indications for surgical intervention. With careful clinical evaluation and proper application of the diagnostic and therapeutic modalities, acute infective endocarditis can often be cured.