Prognostic value of fractional flow reserve: linking physiologic severity to clinical outcomes.

Background: Fractional flow reserve (FFR) has become an established tool for guiding treatment, but its graded relationship to clinical outcomes as modulated by medical therapy versus revascularization remains unclear.

Objectives: The study hypothesized that FFR displays a continuous relationship between its numeric value and prognosis, such that lower FFR values confer a higher risk and therefore receive larger absolute benefits from revascularization.

Methods: Meta-analysis of study- and patient-level data investigated prognosis after FFR measurement.

Bubble stream reveals functionality of the right-to-left shunt: detection of a potential source for air embolism.

The existence of a right-to-left shunt may increase the likelihood of micro-embolism by allowing a flux of bubbles under hyperbaric conditions. The aim of the study was to measure the relationship between these shunts and bubbles in 10 consecutive subjects using trans-thoracic and trans-esophageal echocardiography. In video frames, all cardiac chambers were segmented and bubbles were analyzed by our proposed method and two other methods.

Discard first tube for coagulation testing.

Tissue thromboplastin may contaminate the first tube sample due to the trauma of the venipuncture, and therefore, affect the accuracy of coagulation testing. This practice was stopped by Clinical and Laboratory Standards Institute after several studies. However, most of the studies have verified these conclusions and refuted the need for a discard tube when drawing samples for coagulation tests in healthy groups.

GGT levels in type II diabetic patients with acute coronary syndrome (does diabetes have any effect on GGT levels in acute coronary syndrome?).

Elevated gamma-glutamyltransferase (GGT) level is independently correlated with conditions associated with increased atherosclerosis, such as obesity, elevated serum cholesterol, high blood pressure and myocardial infarction. It is demonstrated that serum GGT activity is an independent risk factor for myocardial infarction and cardiac death in patients with coronary artery disease. Diabetes is also a well-known cardiovascular risk factor and an equivalent of coronary artery disease.

Gamma glutamyltransferase levels and its association with high sensitive C-reactive protein in patients with acute coronary syndromes.

Background: Elevated Gamma-glutamyltransferase (GGT) level is independently correlated with conditions associatedwith increased atherosclerosis, such as obesity, elevated serum cholesterol, high blood pressure and myocardial infarction. It is also demonstrated that serum gamma-glutamyltransferase activity is an independent risk factor for myocardial infarction and cardiac death in patients with coronary artery disease. Although the relationship between gamma-glutamyltransferase and coronary artery disease has been reported, not many studies have shown the relationship between changes ofgamma-glutamyltransferase in acute coronary syndromes and a well established coronary risk factor high sensitive C-reactive protein.

Relationship between carotid intima-media thickness and coronary angiographic findings: a prospective study.

Background: Since cardiovascular diseases are associated with high mortality and generally undiagnosed before the onset of clinical findings, there is a need for a reliable tool for early diagnosis. Carotid intima-media thickness (CIMT) is a non-invasive marker of coronary artery disease (CAD) and is widely used in practice as an inexpensive, reliable, and reproducible method. In the current study, we aimed to investigate prospectively the relationship of CIMT with the presence and extent of significant coronary artery narrowing in patients evaluated by coronary angiography for stable angina pectoris.

Acute effect of cigarette smoking on heart rate variability.

Acute cigarette smoking enhances adrenergic activity and thus may be associated with hemodynamic changes in the cardiovascular system. In this study, the acute effect of cigarette smoking on heart rate variability (HRV) was studied. Fifteen subjects were included in the study.

Acute smoking-induced alterations in Doppler echocardiographic measurements in chronic smokers.

Acute effects of smoking on left ventricular function have been studied previously. However, effects on right ventricular function have not yet been investigated. In this study, we attempted to investigate, through a combination of conventional and tissue Doppler imaging (TDI), the acute effects of smoking on both left and right ventricular function in chronic smokers.

Treatment of aortocoronary graft lesions with graft-stents.

Objective: Previous controlled trials do not indicate a superiority of the polytetrafluoroethylene membrane-covered stent graft compared with a conventional stent with respect to acute results, restenosis, or clinical event rates. We evaluated the outcome of stenting aortocoronary bypass grafts with polytetrafluoroethylene-covered stent.

Methods: The study included 64 patients who had 73 saphenous graft-stent implants.

Cigarette smoking and heart rate variability: dynamic influence of parasympathetic and sympathetic maneuvers.

Background: Cigarette smoking has been associated with increased activity of the sympathetic nervous system. In this study, we investigated cardiac autonomic function in heavy smokers and nonsmoker controls by analysis of heart rate variability (HRV).

Method: Twenty-four long-term heavy smokers (men) and twenty-two nonsmoker subjects (hospital staff) were included to study.

Acute cigarette smoking-induced hemodynamic alterations in the common carotid artery--a transcranial Doppler study--.

Background: Cigarette smoking has been shown to temporarily alter cerebral flow velocity and vasomotor reactivity, so the aim of this study was to assess the acute effects of smoking a single cigarette on the common carotid artery (CCA) hemodynamics in healthy nonsmokers.

Method And Results: Using a 7.0 MHz linear transducer of a computed sonography system, the CCA hemodynamics, including the diameter of the left and right CCA, peak systolic velocity, maximum end-diastolic velocity, time-averaged maximum velocity pulsatility index, resistivity index, flow volume, diameter and area of the CCAs, were measured in 16 healthy nonsmokers before and immediately after smoking a cigarette.

Effect of smoking on endothelial function and wall thickness of brachial artery.

Background: Impaired flow mediated dilatation (FMD) and increased wall thickness (WT) of the brachial artery have been associated with atherosclerosis and its risk factors. In this study we sought to determine brachial artery wall thickness in chronic smokers and the instantaneous effect of smoking on brachial artery endothelium dependent vasodilator function in smokers and non-smokers.

Method And Results: Using a high-resolution ultrasound, WT of posterior brachial artery wall, the diameter of brachial artery at rest and during reactive hyperemia (FMD %), as well as after sublingual administration of nitroglycerine (nitroglycerine mediated dilatation (NMD) %) was measured in 20 smokers and 20 non-smokers.