Chronobiologically Explored Effects of Telmisartan

Effects of Micardis (Telmisartan), alone or with low-dose aspirin, on blood pressure and other cardiovascular endpoints are examined in 20 patients with MESOR-hypertension in a crossover, double-blind, randomized study consisting of three stages, each lasting 7 days: I-placebo, II-Micardis, and III-Micardis with low-dose aspirin. Treatment was administered each day at a different circadian stage, upon awakening, and 3, 6, 9, 12, 15 and 18 hr after awakening. During each stage, the following variables were measured at 3-hr intervals during waking: systolic and diastolic blood pressure, heart rate, ejection fraction, intrarenal resistive index, acceleration time, and serum creatinine. Each data series was analyzed by single cosinor. Results were summarized by population-mean least squares spectra. At matched treatment times, the MESOR and circadian amplitude of each variable were compared among the three treatments by paired t-tests. A prominent circadian rhythm characterizes all variables. Micardis was associated not only with a lowering of blood pressure, but also with a reduction of the circadian blood pressure amplitude. The ejection fraction was increased, and the resistive index and acceleration time were decreased, the effect being more pronounced when low-dose aspirin was added to Micardis. Any circadian-stage dependent effect of Micardis, with or without low-dose aspirin, will require monitoring over spans longer than a single day for a given treatment administration time.     

Correlation of serum ST2 levels with severity of diastolic dysfunction on echocardiography and findings on cardiac MRI in patients with heart failure with preserved ejection fraction

ObjectiveThe aim of the present study was to find a correlation of serum Suppression of tumorigenicity 2 (ST2) levels with severity of diastolic dysfunction on echocardiography and cardiac magnetic resonance imaging (CMRI) in heart failure with preserved ejection fraction (HFpEF) patients.MethodsFifty patients aged ≥18 years fulfilling diagnostic criteria for HFpEF were included. ST2 levels, 2D echocardiography and CMRI were performed. Left ventricular ejection fraction, E/A, Septal E/E’, left atrial volume index (LAVI), tricuspid regurgitation (TR), assessment of diastolic dysfunction, T1 mapping in milliseconds and late gadolinium enhancement (LGE) in percentage were noted. The primary outcome measure was to study correlation of ST2 levels with severity of diastolic dysfunction, whereas the secondary outcome measures were to study correlation of ST2 levels with native T1 mapping and LGE on CMRI.ResultsST2 levels showed statistically significant and positive correlation with E/E’ (r = 0.837), peak TR velocity (r = 0.373), LAVI (r = 0.74), E/A (r = 0.420), and T1 values in milliseconds (r = 0.619). There was no statistically significant correlation between ST2 level and LGE in % (r = 0.145). The median ST2 levels in patients with E/E’ > 14 and E/E’ ≤ 14 were 110.8 and 36.1 respectively (p-value < 0.05). The mean ST2 levels were significantly higher in patients who had diastolic dysfunction grade III (126.4) and New York Heart Association class IV (133.3).ConclusionsEvaluation of ST2 adds important information to support the diagnosis of left ventricular diastolic dysfunction in patients with HFpEF.     

Is ivabradine suitable to control undesirable tachycardia induced by dobutamine in cardiogenic shock treatment?

Inotropic treatment remains the cornerstone for cardiogenic shock, an emergency that requires immediate resuscitative therapy before shock irreversibly damages vital organs. Although the sympathomimetic drug dobutamine is the most widely-used inotropic drug worldwide, it has several side effects including sinus tachycardia. Dobutamine partly restores systolic heart failure (HF); however, it increases the heart rate (HR) which counterbalances the beneficial effects. Ivabradine, a new selective I_f inhibitor, provides specific HR reduction and is indicated in stable coronary artery disease and in stable chronic HF with left ventricular dysfunction. Despite scarce data indicating beneficial effects of ivabradine in sinus tachycardia in various clinical settings, this drug remains contraindicated in acute HF. We propose that ivabradine could help to prevent the dobutamine-induced side effects, and that their combination in clinical practice could lead to pure inotropic effects, useful for the management of cardiogenic shock.     

Three-Dimensional Echocardiography in Evaluation of Left Ventricular Indices

Accurate determination of left ventricular mass, volume, ejection fraction, and wall motion is important for clinical decision making. Currently, M-mode and two-dimensional echocardiography (2DE) have been routinely used for this purpose. Although these 1D or 2D modalities provide excellent diagnostic and prognostic information, they have a number of technical limitations including the time required to perform the procedure and operator-dependent image acquisitions. In addition, they are inherently limited by geometric assumption of three-dimensional (3D) left ventricular structures based on 2D slices. With the improvement in transducer technology and software development, 3D echocardiography (3DE) has become widely available. Left ventricular quantitation by 3DE has been demonstrated to be accurate by multiple studies that compared 3DE with reference techniques. In addition, 3DE measurements were found to be more reproducible and less variable than 2DE. Real time 3DE imaging has potential advantages in stress echocardiography including rapid acquisition, unlimited number of planes, avoidance of foreshortening, and precise segment matching. This is a major step forward in our diagnostic armamentarium for the evaluation of ischemia. In this review, we summarized the current evidence of 3DE for left ventricular evaluation. (Echocardiography 2012;29:66-75)     

Ventricular performance and prognosis after primary ventricular fibrillation complicating acute myocardial infarction

To examine the relationship between early arrhythmias, infarctsize and prognosis, we compared 22 consecutive patients survivingacute myocardial infarction (AMI) and primary ventricular fibrillation(VF) with a control population after AMI uncomplicated by primaryVF. Left ventricular ejection fraction (EF) was measured byradionuclide ventriculography before discharge from hospital.Mean EF was significantly reduced below normal following AMIwith or without primary VF (normal 0.57±0.05, mean±SD;P<0.01). Mean EF was lower among patients who survived primaryVF than among those with infarction uncomplicated by primaryarrhythmia (0.33 ±0.12 v. 0.46 ±0.07; P<0.01).There were striking differences in EF between those patientswith anterior and those with inferior infarction. Mean EF forthose surviving primary VF after transmural anterior infarction(0.23±0.06) was lower than those who had primary VF aftertransmural inferior infarction (0.43±0.06; P<0.01J.Normal left ventricular function was seen in four individualswho developed no further complications. Recurrent primary ventriculararrhythmia was seen v only in those individuals subsequentlyshown to have reduced EF. Low EF (< 0-35) was seen in 12patients with primary VF in the context of anterior infarction,five developed breakthrough ventricular arrhythmias despitetherapy and in a limited follow-up period, three have died.