Unmasking pulmonary hypertension following tricuspid valve replacement.

In this Viewpoint, we highlight a possible hemodynamic problem arising following tricuspid valve replacement (TVR) in patients with severe chronic tricuspid regurgitation, represented by "unmasking" of pulmonary hypertension (PH) following the surgery. We share an observation that should alert cardiologists to the fact that this increasingly utilized surgery is not risk free, and careful assessment of the right ventricular function and pulmonary circulation preoperatively is extremely important, especially in patients with preexisting risk factors for PH, since TVR may lead to a sudden increase in right ventricular afterload.

Giant Calcified Left Circumflex Coronary Artery Aneurysm With Complex Coronary-to-Left Ventricular Communication.

A 64-year-old asymptomatic man had an incidental finding of a giant left circumflex artery (LCX) aneurysm, with the distal LCX draining into a confluence receiving terminal portions of all coronary arteries and communicating with the left ventricle through a transmural fistulous tract. We believe that this is the first case reported with such a complex LCX abnormality. (Level of Difficulty: Beginner.).

Cardiovascular manifestations in human immunodeficiency virus-infected patients.

Human immunodeficiency virus (HIV) is now a pandemic. It afflicts multiple organs, including the cardiovascular system. This occurs by direct invasion as well as opportunistic infections complicating acquired immunodeficiency syndrome. The presence of newer highly active antiretroviral therapy has led to longer survival of patients infected with HIV, but the cardiac abnormalities related to HIV have remained less well characterized. It is now evident that cardiac involvement in patients with acquired immunodeficiency syndrome is relatively common. This includes coronary artery disease, dilated cardiomyopathy, pericardial effusion, pulmonary hypertension, and ill effects of highly active antiretroviral therapy in the form of lipodystrophy, lipoatrophy, and dyslipidemia. In fact, HIV can now be viewed as a potential risk factor for coronary artery disease, and the dilemma facing clinicians is how to quantify this risk. Awareness of accelerated coronary artery disease and dilated cardiomyopathy is critical to implement preventive measures early in the course of HIV. However, better guidelines are still needed on the basis of prospective randomized controlled studies involving large populations. In conclusion, this review describes cardiac abnormalities associated with HIV, including possible molecular mechanisms. The co-morbid sequelae, their presentation, and pharmacologic management are also discussed.

Hemodynamic collapse during left ventricular lead implantation.

Hypotension as a procedural complication during cardiac resynchronization therapy (CRT) implantation was reported in the initial randomized clinical trials. However, this phenomenon is not well characterized. We reviewed our CRT implantation experience to better understand this issue. There were 105 patients who underwent left ventricular lead implantation for CRT. Four patients had marked hypotension (systolic blood pressure < or = 50 mmHg) during the procedure. All had a history of hypertension and diabetes mellitus and were pacemaker dependent. Two had normal renal function, one had moderate renal insufficiency, and one was on dialysis. Three patients had ischemic cardiomyopathy. All had left ventricular ejection fraction < or =20% and were in New York Heart Association class III. Propofol and midazolam were used for sedation as standard protocol. Two patients had sudden hypotension when the coronary sinus was being cannulated, and two patients experienced sudden hypotension during left ventricular pacing. Cardiac tamponade as a possible cause was ruled out by echocardiography. We discuss possible mechanisms of sudden hemodynamic collapse during CRT implantation.