Usefulness of echocardiographic tissue synchronization imaging to predict acute response to cardiac resynchronization therapy

Echocardiographic tissue synchronization imaging (TSI) consists of color-coding time-to-peak tissue Doppler velocities. This study of 29 patients who underwent cardiac resynchronization therapy (CRT) demonstrated that differences in baseline time-to-speak velocities of opposing ventricular walls by TSI were greater in 15 patients, with an acute hemodynamic improvement. A >/=65 ms delay from the anterior septum to the posterior wall using the apical long-axis view had 87% sensitivity and 100% specificity for predicting an acute response. Although a subgroup without acute improvement had later decreases in end-systolic volume, suggesting that acute response underestimates long-term effects, TSI has potential to assist in guiding CRT.     

Catheter Ablation to Suppress Atrial Fibrillation: Evolution of Technique at a Single Center

Background: Catheter ablation of atrial fibrillation is a rapidly evolving art. There is currently no consensus as to optimal methodology. We report a sequential experience, during which three distinct ablation techniques were utilized. Methods: A cohort of 112 patients in whom atrial fibrillation onset was precipitated by ectopy arising solely from myocardium investing the pulmonary veins underwent catheter ablation using one of three techniques: focal (Group A); individual vein encircling (Group B); vestibule encircling (Group C). In each group, non-fluoroscopic guidance of the mapping and ablation process was provided by the tandem use of CARTO^RM and intracardiac echocardiography. Results: In all groups, endocardial topography was complex, and ablation electrode-endocardial contact was often unstable. Maximal electrode temperatures were low, despite frequent echocardiographic evidence of myocardial boiling. A significant progression in the number of radiofrequency energy applications between groups A and C was observed. Although acute suppression of atrial fibrillation inducibility was observed uniformly, chronic suppression rates were significantly different: Group A = 47%; Group B ; 69%; Group C = 87%. Conclusions: In this non-concurrent cohort, the rate of chronic suppression of atrial fibrillation correlated with the amount of myocardium ablated or electrically isolated. Prospective data will be required to further evaluate whether more is better.     

Population data and genetic characteristics of 12 X-STR loci using the Investigator® Argus X-12 Quality Sensor kit for the Kedayan population of Borneo in Malaysia

International Journal of Legal Medicine - DNA profiling of X-chromosomal short tandem repeats (X-STR) has exceptional value in criminal investigations, especially for complex kinship and incest...     

Recombinant Human Interleukin-1 Receptor Antagonist Provides Cardioprotection During Myocardial Ischemia Reperfusion in the Mouse

Purpose

Acute myocardial infarction (AMI) drives an intense inflammatory response that contributes to infarct healing and cardiac remodeling. Recently, different studies have identified a role of interleukin-1 (IL-1) in the development of adverse cardiac remodeling. However, in animal models of AMI IL-1 has been shown to be cardioprotective in preconditioning, raising the question of clinical safety of therapeutic IL-1 blockade for autoinflammatory diseases or for the prevention or the treatment of AMI. In this study we proposed to evaluate the effects of pretreatment with recombinant human interleukin-1 receptor antagonist (rhIL-1Ra) on ischemia reperfusion (I/R) injury to the heart.

Methods

RhIL-1Ra was given 4?h or 30?min before the surgical induction of I/R. Left ventricular ejection fraction(LVEF) and infarct size were assessed to determine the effects of the drug pretreatment compared to vehicle treated mice.

Results

RhIL-1Ra, given 4?h or 30?min before the onset of the ischemia, showed marked cardioprotection though preservation of the LVEF (no change vs sham operated mice) and the reduction of the infarct size (?40?% vs vehicle-treated mice). No differences were observed between the two groups of rhIL-1Ra treatment.

Conclusions

IL-1 blockade therapies using rhIL-1Ra prior the onset of AMI protects the myocardium and preserves cardiac function.     

Two new alpha-thalassemia frameshift mutations

alpha-Thalassemia (thal) is common all over the world. Most of the mutations encountered are of the deletional type. We now report two frameshift alpha-thal mutations: a novel alpha1-globin gene deletion at codon 62 (GTG -->-TG) found in an African American man, and a second report on an alpha2-globin gene deletion at codon 22 (GGC-->GG -) found in a Hispanic girl.     

Differential strain and velocity generation along the right ventricular free wall in pulmonary hypertension

BACKGROUND:

In contrast to the homogeneously distributed deformation properties within the left ventricle, the right ventricular (RV) free wall (RVFW) shows a more inhomogeneous distribution. It has been demonstrated that pulmonary hypertension (PH) results in significant RVFW mechanical delay.

OBJECTIVE:

To assess the effect of the degree of pulmonary arterial systolic pressure on the RVFW strain gradient and on myocardial velocity generation.

METHODS:

Peak longitudinal strain and velocity data were collected from three different segments (basal, mid- and apical) of the RVFW in 17 normal individuals and 31 PH patients.

RESULTS:

A total of 144 RV wall segments were analyzed. RVFW strain values in individuals without PH were higher in the mid and apical segments than in the basal segment. In contrast, RVFW strain in PH patients was higher in basal segments and diminished toward the apex. In terms of RVFW velocities, both groups showed decremental values from basal to apical segments. Basal and mid-RVFW velocities were significantly lower in PH patients than in individuals without PH.

CONCLUSIONS:

PH results in significant alterations of strain and velocity generation that occurs along the RVFW. Of these abnormalities, the reduction in strain from the mid and apical RVFW segments was most predictive of PH. It is important to be aware of these differences in strain generation when studying the effect of PH on the right ventricle. Additional studies are required to determine whether these differences are due to RV remodelling.