The Tree of Sirtuins and the Garden of Cardiovascular Youth.

Sirtuins (SIRTs) are a class of nicotine adenine dinucleotide (NAD+)-dependent proteins which participate in numerous molecular pathways involved in various age-related human diseases, such as type II diabetes, cardiovascular (CV) diseases and cancer. They have a major role in apoptosis, inflammation, oxidative stress and metabolism regulation, traits that have a great impact on CV physiology and pathology. Their unique profile of NAD+ energy dependency makes them an appealing target for human intervention in cellular and metabolic processes. This review focuses on the recent advances of SIRTs research aiming to shed light on the emerging roles of SIRTs in the pathophysiology of CV and metabolic diseases.

Correlation of arm position and exercise test interpretation.

ST-segment changes during exercise testing can be attributed mainly to ischemia, but also, in some patients, to other physiological parameters, such as body position or hyperventilation, making ECG exercise test interpretation more complex. Here we describe the case of a patient who had an electrocardiographically positive exercise test, in order to illustrate the correlation between arm position and ST changes during exercise testing.

The impact of novel exercise criteria and indices for the diagnostic and prognostic ability of exercise testing.

Exercise testing (ET) stands as one of the most easy, affordable, cost effective, non invasive methods for diagnosing coronary heart disease. Its sensitivity, specificity and prognostic value, especially in the prime era of its implementation in the cardiac diagnostic procedure, is relatively limited. Novel exercise criteria and indices based either on ST segment changes or ST segment independent parameters, such as "Athens QRS score", have greatly improved the diagnostic ability and accuracy of ET. Complex ECG-derived indices linked to ST changes along with the use of right-sided precordial leads have also enhanced the diagnostic accuracy of ET with respect to the extent of ischemic heart disease and the detection of specific culprit vessels. ET contains also a prognostic value, since several ET-derived parameters have been associated with adverse outcome, including ST changes, blood pressure and heart rate response to exercise and duration of exercise.

Right-sided chest leads in exercise testing for detection of coronary restenosis.

BACKGROUND: The incorporation of right-sided chest leads (V(3)R through V(5)R) into standard exercise testing has been reported to improve its diagnostic utility. HYPOTHESIS: The purpose of this study was to evaluate any improvement in the ability of exercise testing in detecting restenosis, using additional V(3)R through V(5)R leads, in asymptomatic patients undergoing percutaneous coronary intervention (PCI) in the right coronary artery (RCA) or/and left circumflex (LCX). METHODS: We studied 172 consecutive patients (54 +/- 7 years old, 106 males) undergoing PCI in RCA or/and LCX. A treadmill test had been performed before PCI. Six months later, all patients underwent a second treadmill test and arteriography in order to detect silent ischemia due to restenosis. Recordings during exercise were obtained with the standard 12-leads plus V(3)R through V(5)R. RESULTS: Out of 172 patients, 106 had stenosis in RCA, 35 in LCX, and 31 in both vessels while 6 months later, restenosis was detected in 8 (for RCA), 3 (for LCX), and 3 (for both vessels) patients respectively. Sensitivity, specificity, positive prognostic value, negative prognostic value, and accuracy of exercise testing performed post PCI were ameliorated using V(3)R through V(5)R (79% vs 57%, 97% vs 80%, 69% vs 21%, 98% vs 95%, and 95% vs 78% respectively, P < .05 for all except negative prognostic value). Maximal exercise-induced ST-segment deviation (in mm) was not changed post PCI in 12 leads (1.4 +/- 0.2 vs 1.5 +/- 0.2, P = NS) while it was decreased in V(3)R through V(5)R (0.2 +/- 0.2 vs 1.2 +/- 0.3, P < .01). CONCLUSIONS: The addition of V(3)R through V(5)R improves the diagnostic ability of standard exercise testing in detecting silent ischemia due to restenosis in patients undergoing PCI in RCA or/and LCX.

Correlation of ST-segment "hump sign" during exercise testing with impaired diastolic function of the left ventricle.

BACKGROUND: The appearance of a discrete upward deflection of the ST segment, termed the ST hump sign during exercise testing has been associated with resting hypertension and exaggerated blood pressure response to exercise. OBJECTIVE: We investigated the correlation between the presence of hump sign during exercise testing with coexisting impaired diastolic function of the left ventricle (LV) at these patients. METHODS: We formed a cohort of 237 nonconsecutive patients (140 males, 41 +/- 5 years old) having undergone a treadmill test, according to the Bruce protocol, which divided into 2 groups: group A, including 130 patients which presented ST-segment hump sign at any of the leads of the electrocardiograms recorded during exercise, and group B, including 107 patients that didn't. All patients subsequently underwent an echocardiographic estimation of the LV diastolic function, using conventional and Tissue Doppler Imaging techniques. RESULTS: From 237 patients included in our study, 106 had echocardiographic signs of diastolic LV dysfunction. Among them, the appearance of ST hump sign at the peak of exercise testing was observed in 93 patients (88%), particularly in the inferior and lateral leads, while no ST hump sign was observed only in 13 patients (12%) with impaired diastolic LV function. CONCLUSIONS: The appearance of ST segment hump sign during exercise testing is strongly correlated with diastolic LV dysfunction and can be used as an exercise electrocardiographic index of diastolic LV dysfunction, independently from the echocardiographic study.

Electrocardiographic criteria for detecting coronary artery disease in hypertensive patients with ST-segment changes during exercise testing.

PURPOSE: It is well known that patients with arterial hypertension frequently present with ischemic electrocardiographic changes during exercise testing without actually having coronary artery disease (CAD). The purpose of this study was to establish additional electrocardiographic criteria during exercise testing for detecting CAD in hypertensive patients with ischemic ST-segment response. METHODS: Three hundred eighty-two consecutive hypertensive patients (224 males, 58 +/- 8 years) who presented with ischemic electrocardiographic changes during exercise testing and agreed to undergo coronary arteriography were included in the study. RESULTS: From 382 hypertensive patients undergoing coronary angiography, only 76 (20%) had significant coronary stenosis, whereas 306 (80%) had normal coronary arteries. From 382 patients, 287 (75%) (group A) presented with ST-segment depression during exercise in leads II-III-aVF-V(6), 271 (94%) of which had normal arteries at the angiography. The remaining 95 patients (25%) (group B) of the studied patients presented with ST-segment depression in II-III-aVF and/or V(4) through V(6), 60 (63%) of which had CAD. Furthermore, 251 patients of group A presented with ST-segment depression during the fourth to sixth minute of the recovery period in V(4) through V(6), 247 (98%) of which had normal arteries. Another 28 patients from group B presented with ST-segment depression during the fourth to eighth minute of the recovery period in V(4) through V(6), 22 (79%) of which had significant coronary artery stenosis. CONCLUSIONS: Hypertensive patients who present with ST-segment depression during exercise in leads II-III-aVF and/or V(4) through V(6) and with a prolonged duration of this depression at the recovery phase (fourth to eighth minute) are more likely to have CAD. Absence of ST-segment depression in V(4) and V(5) at the end of exercise or during the seventh and eighth minute of recovery favors a false-positive result.

A case of pseudomembranous colitis presenting with massive ascites.

Clostridium difficile-associated disease seems to be increasing worldwide. A wide spectrum of clinical manifestations, ranging from asymptomatic to life-threatening disease, has been described. A case of pseudomembranous colitis with massive ascites as the main presenting manifestation is described in order to illustrate the changing clinical pattern of antibiotic-associated colitis.