Biventricular pacemaker upgrade in previously paced heart failure patients--improvements in ventricular dyssynchrony

BackgroundCardiac resynchronization therapy (CRT) reduces symptoms and mortality in patients with left bundle branch block (LBBB) and severe chronic heart failure. There are few data demonstrating the effects of CRT on contemporary dyssynchrony variables in patients with advanced heart failure who have been chronically paced from the right ventricle (RV).Methods and ResultsWe reviewed baseline and follow-up clinical and echocardiographic data on patients receiving CRT in a single centre. Indices of global left ventricular (LV) function and dyssynchrony before and after CRT were measured. Patients were then divided into those receiving their first device (n = 39) and those receiving CRT as an upgrade to existing RV pacemakers (n = 32). Baseline demographic variables, indices of global LV function, symptomatic status, renal function, hemodynamics, and diuretic requirements were not different between previously paced patients and nonpaced patients. Mean length of RV pacing in the previously paced patients was 59 months (range 12–167 months). Patients in the previously paced group had a broader QRS complex than patients with intrinsic LBBB. Aortopulmonary delay of longer than 40 ms was present in 68% of all subjects, 67% had intraventricular septal and posterior wall motion delay longer than 130 ms, and 59% had an intraventricular delay as measured by tissue Doppler imaging of longer than 65 ms. There was no difference between paced and nonpaced patients for any of these measures of dyssynchrony. QRS duration was reduced to a greater extent in the previously paced patients than those with no previous device therapy. CRT led to important reductions in each dyssynchrony variable in both patients with previous RV pacing and those with intrinsic LBBB. The magnitude of these changes in measures of dyssynchrony was not different between the 2 groups. In all patients undergoing CRT, 50% had a reduction in furosemide dose at 3 months, 56% an improvement of at least 1 grade in New York Heart Association status, and 66% an improvement of at least 5% in LVEF. Divided by group, previously paced patients were no more or less likely than newly implanted patients to achieve one or more of these clinical outcomes.ConclusionOur data suggest that patients with RV pacing and heart failure have similar dyssynchrony as patients with intrinsic LBBB. CRT leads to improvements in LV global function, dyssynchrony variables and symptoms in patients chronically paced from the RV that are similar to those observed in patients with LBBB without preexisting devices.     

Bicentric bipolar hip prosthesis: A radiological study of movement at the interprosthetic joint

Background:

The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals.

Materials and Methods:

Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint.

Results:

In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients), which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value) and at 1.5 years it was 67.52%.

Conclusion:

This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.     

Relationship of Psychosocial Risk Factors, Certain Personality Traits and Myocardial Infarction in Indians: A Case�Ccontrol Study

Objective:

To investigate the relationship of psychosocial factors (lack of social support, stress and subjective well-being) and personality traits with myocardial infarction (MI).

Materials and Methods:

A case–control study involving 100 cases and 100 matched controls was conducted in Lok Nayak Hospital, New Delhi.

Results:

Stress over 1 year was significantly higher in cases (P < 0.001). However, difference was not significant when scores of social support (P = 0.2), Presumptive Stressful Life Event (PSLE) over lifetime (P = 0.058) and subjective well-being (P = 0.987) were compared. MI was significantly associated with hyperactive (P < 0.001), dominant (P = 0.03), egoistic (P < 0.001) and introvert (P < 0.001) personalities.

Conclusion:

Certain personality traits and recent stress may be important risk factors of MI, especially in Indians. The finding may have implications on the preventive strategies planned for MI patients.     

Health Care Utilization After Ventricular Tachycardia Ablation: A Propensity Score-Matched Cohort Study

Background

Catheter ablation of ventricular tachycardia (VT) can reduce the burden of ventricular arrhythmia (VA) but its effect on health care utilization and costs after such therapy is poorly known. We sought to compare the rates of cardiovascular (CV)-related hospitalizations, survival, and health care costs in patients with recurrent VT treated either with VT ablation or with medical therapy.

Antioxidant, cytotoxic and genotoxic evaluation of alcoholic extract of Polyalthia cerasoides (Roxb.) Bedd

Antioxidative potential of alcohol extract of Polyalthia cerasoides was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical, superoxide anion scavenging, and reducing power assays were performed. The extract showed significant reactive oxygen species (ROS) scavenging activity in all in vitro antioxidant assays and contained high level of total phenolic content. For in vivo genotoxic evaluation, Swiss albino mice were treated with alcohol extract at the concentration of 40mg/kg body weight. Frequency of aberration was compared with control. Both the sets did not showed genotoxic effect. Further the extract was subjected to cytotoxic study using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphynyl tetrazolium bromide (MTT) assay, the extract confirmed to show moderate cytotoxicity against L929 cell line.     

“Transport Distraction Osteogenesis for Reconstruction of Mandibular Defects”: Our Experience

Introduction  

Mandibular defects usually involve a combination of osseous and soft tissue deficiency and are among the most challenging problems in maxillofacial surgery, many options are available for mandibular reconstruction. One of the options discussed in literature recently being distraction osteogenesis.