Ranjit S More

Aging-Associated Endothelial Dysfunction in Humans Is Reversed by L-Arginine *

OBJECTIVES This study investigated the hypothesis that aging selectively impairs endothelium-dependent function, which may be reversible by administration of L-arginine. BACKGROUND An impaired response to acetylcholine with aging has been demonstrated in humans. However, the mechanisms underlying this impaired response of the coronary microvasculature remain to be determined. METHODS We infused the endothelium-independent vasodilators papaverine and glyceryl trinitrate (GTN) and the endothelium-dependent vasodilator acetylcholine (1,3,10 and 30 micrograms/min) into the left coronary artery of 34 patients (27 to 73 years old) with atypical chest pain, negative exercise test results, completely normal findings on coronary angiography and no coronary risk factors. Coronary blood flow was measured with an intracoronary Doppler catheter. The papaverine and acetylcholine infusions were repeated in 14 patients (27 to 73 years old) after an intracoronary infusion of L-arginine (160 mumol/min for 20 min). RESULTS There was a significant negative correlation between aging and the peak coronary blood flow response evoked by acetylcholine (r = -0.73, p < 0.0001). However, there was no correlation to papaverine (r = -0.04, p = 0.82) and GTN (r = -0.24, p = 0.17). The peak coronary blood flow response evoked by acetylcholine correlated significantly with aging before L-arginine infusion (r = -0.87, p < 0.0001), but this negative correlation was lost after L-arginine infusion (r = -0.37, p = 0.19). CONCLUSIONS The results suggest that aging selectively impairs endothelium-dependent coronary microvascular function and that this impairment can be restored by administration of L-arginine, a precursor of nitric oxide.

Higher Energy Monophasic DC Cardioversion for Persistent Atrial Fibrillation: Is it Time to Start at 360 Joules?

Background: Electrical direct‐current cardioversion (DCCV) has become a routine therapy for atrial fibrillation (AF), although some uncertainty remains regarding the optimal energy settings.

Persistent atrial fibrillation: rate control or rhythm control

Rate control is not inferior to rhythm control

GPIIbIIIa inhibitors as adjunctive therapy in acute myocardial infarction

Thrombolytic therapy has proved useful in the treatment of acute myocardial infarction but is frequently associated with limited vessel reperfusion and early reocclusion. Local platelet aggregation and activation play a role in these pathological processes, explaining the benefit of aspirin, a weak antiplatelet agent. Recent interest has turned to GPIIbIIIa antagonists, a class of potent inhibitors of platelet aggregation. Their concomitant use with fibrinolytics, in rescue and primary angioplasty for acute myocardial infarction treatment is explored. Efficacy and safety issues are addressed and the potential pivotal role of these agents in the treatment of acute myocardial infarction is discussed.

Giant unruptured Sinus of Valsalva aneurysm: an unusual cause of aortic regurgitation

Sinus of Valsalva aneurysm (SVA) is rare (0.15%–1.5% of cardiopulmonary bypass cases) and usually presents acutely following rupture. Unruptured SVA is usually asymptomatic, but can lead to symptoms secondary to compression of adjacent cardiac structures. Ruptured SVA can lead to aortocardiac shunts and heart failure. About 65%–85% of SVAs originate from the right sinus, 10%–30% from non-coronary sinus and less than 5% from left …

Unusual presentation of endocarditis as inferior STEMI

A 70-year-old man presented with inferior STEMI. Coronary angiography showed an occluded circumflex artery (Cx) ( Panel A , Supplementary material, Video S1 ). The post-thrombectomy TIMI 3 flow was established instantly ( Panel B , Supplementary material, Video S2 ) . There was no evidence of an underlying stenotic atheromatous plaque, raising possibility of an embolic phenomenon. He gave a 3-week history of malaise, generalized arthralgia, progressive loss of vision, …

The role of coronary angioplasty and stenting in acute myocardial infarction

Despite the improvements in the pharmacological treatment of acute myocardial infarction, it is recognised that thrombolysis fails to reproduce reperfusion in a significant proportion of patients. Coronary interventional techniques have been shown to offer an alternative reperfusion strategy. There is increasing evidence that mechanical reperfusion may offer significant advantages over established thrombolytic therapy.

Balloon assisted retraction of a migrated CoreValve Evolut R bioprosthesis during cardiac arrest

We describe a case of balloon assisted retraction of a migrated CoreValve Evolut R bioprosthesis during trans-femoral TAVI.

Direct thrombin inhibitors: novel antithrombotics on the horizon in the thromboprophylactic management of atrial fibrillation

Antithrombotic agents have verified efficacy in reducing the thromboembolic risk associated with atrial fibrillation. This article focuses on the emergence of a new oral direct thrombin inhibitor, ximelagatran, into the arena of atrial fibrillation thromboprophylaxis. This review does not cover atrial fibrillation in the context of valvular heart disease. The efficacy of aspirin and warfarin will be discussed briefly.

Antiplatelet use in interventional cardiology

Thrombosis within the target vessel is one of the most feared complications associated with coronary intervention, as it is often associated with severe adverse clinical sequelae. This thrombosis is mediated via the activation and aggregation of platelets and therefore considerable effort has been directed at ways of inhibiting platelet function. It is now mandatory to consider the use of two and often three different antiplatelet agents, particularly when intracoronary stents are inserted. Using these regimes, many of the adverse clinical outcomes associated with platelet activation can be reduced.