Archive

Archive for July, 2012

Journal Club 25 July 2012

Paper

Azithromycin and the Risk of Cardiovascular Death

Presenter

LAM

Summary

Abstract from paper:

BACKGROUND

Although several macrolide antibiotics are proarrhythmic and associated with an increased
risk of sudden cardiac death, azithromycin is thought to have minimal cardiotoxicity.
However, published reports of arrhythmias suggest that azithromycin
may increase the risk of cardiovascular death.

METHODS

We studied a Tennessee Medicaid cohort designed to detect an increased risk of death
related to short-term cardiac effects of medication, excluding patients with serious
noncardiovascular illness and person-time during and shortly after hospitalization.
The cohort included patients who took azithromycin (347,795 prescriptions),
propensity-score–matched persons who took no antibiotics (1,391,180 control periods),
and patients who took amoxicillin (1,348,672 prescriptions), ciprofloxacin
(264,626 prescriptions), or levofloxacin (193,906 prescriptions).

RESULTS

During 5 days of therapy, patients taking azithromycin, as compared with those who
took no antibiotics, had an increased risk of cardiovascular death (hazard ratio, 2.88;
95% confidence interval [CI], 1.79 to 4.63; P<0.001) and death from any cause (hazard
ratio, 1.85; 95% CI, 1.25 to 2.75; P = 0.002). Patients who took amoxicillin had
no increase in the risk of death during this period. Relative to amoxicillin, azithromycin
was associated with an increased risk of cardiovascular death (hazard ratio,
2.49; 95% CI, 1.38 to 4.50; P = 0.002) and death from any cause (hazard ratio, 2.02;
95% CI, 1.24 to 3.30; P = 0.005), with an estimated 47 additional cardiovascular deaths
per 1 million courses; patients in the highest decile of risk for cardiovascular disease
had an estimated 245 additional cardiovascular deaths per 1 million courses.
The risk of cardiovascular death was significantly greater with azithromycin than
with ciprofloxacin but did not differ significantly from that with levofloxacin.

CONCLUSIONS

During 5 days of azithromycin therapy, there was a small absolute increase in cardiovascular
deaths, which was most pronounced among patients with a high baseline
risk of cardiovascular disease.

Appendix information is available here.

Journal Club 18 July 2012

Paper

Echocardiographic Evaluation of Hemodynamics in Patients With Decompensated Systolic Heart Failure

Presenter:

SP

Summary

Results

Consecutive patients with decompensated heart failure had simultaneous assessment of left ventricular
and right ventricular hemodynamics invasively and by Doppler echocardiography. In 79 patients, the noninvasive
measurements of stroke volume (r0.83, P0.001), pulmonary artery systolic (r0.83, P0.001) and diastolic pressure
(r0.51, P0.009), and mean right atrial pressure (r0.85, P0.001) all had significant correlations with invasively acquired measurements. Several Doppler indices had good accuracy in identifying patients with pulmonary capillary wedge pressure 15 mm Hg (area under the curve, 0.86 to 0.92). The recent American Society of Echocardiography/European Association of Echocardiography guidelines were highly accurate (sensitivity, 98%; specificity, 91%) in identifying patients with increased wedge pressure. In 12 repeat studies, Doppler echocardiography readily detected the changes in mean wedge pressure (r0.75, P0.005) as well as changes in pulmonary artery systolic pressure and mean right atrial pressure.

Conclusions

Doppler echocardiography provides reliable assessment of right and left ventricular hemodynamics in
patients with decompensated heart failure.

Comments

  • A number of participants observed the paucity of evidence supporting routine assessment of hemodynamics in guiding therapy for chronic heart failure (including papers by Lynne Warner Stevenson).
  • The consistent relationship of hemodynamics  and prognosis was noted
  • The paper choice was motivated by a planned research project
  • The chpice of LVEDP pre-a wave for comparison with non-invasive data was noted to be largely based on expert opinion and would also be looked at in proposed study

Journal club 11 July 2012

Paper

Early Surgery versus Conventional Treatment for Infective Endocarditis

Presenter

AL

Summary:

BACKGROUND
The timing and indications for surgical intervention to prevent systemic embolism in
infective endocarditis remain controversial. We conducted a trial to compare clinical
outcomes of early surgery and conventional treatment in patients with infective
endocarditis.
METHODS
We randomly assigned patients with left-sided infective endocarditis, severe valve
disease, and large vegetations to early surgery (37 patients) or conventional treatment
(39). The primary end point was a composite of in-hospital death and embolic
events that occurred within 6 weeks after randomization.
RESULTS
All the patients assigned to the early-surgery group underwent valve surgery within
48 hours after randomization, whereas 30 patients (77%) in the conventional-treatment
group underwent surgery during the initial hospitalization (27 patients) or
during follow-up (3). The primary end point occurred in 1 patient (3%) in the earlysurgery
group as compared with 9 (23%) in the conventional-treatment group (hazard
ratio, 0.10; 95% confidence interval [CI], 0.01 to 0.82; P = 0.03). There was no
significant difference in all-cause mortality at 6 months in the early-surgery and
conventional-treatment groups (3% and 5%, respectively; hazard ratio, 0.51; 95% CI,
0.05 to 5.66; P = 0.59). The rate of the composite end point of death from any cause,
embolic events, or recurrence of infective endocarditis at 6 months was 3% in the
early-surgery group and 28% in the conventional-treatment group (hazard ratio,
0.08; 95% CI, 0.01 to 0.65; P = 0.02).
CONCLUSIONS
As compared with conventional treatment, early surgery in patients with infective
endocarditis and large vegetations significantly reduced the composite end point of
death from any cause and embolic events by effectively decreasing the risk of systemic
embolism.

Comments

  • The selective nature of the patients was noted: hemodynamically significant valve lesions with large vegetations from largely low virulence organisms in a  group with high baseline prevalence of embolic phenomena
  • The observed composite end point difference in favor of early surgery was driven by embolic events
  • The high prevalence of clinical embolic phenomena in the conservative arm was noted
  • It remains an open question as to the management of patients with large vegetations without hemodynamically significantly valve lesion, though the second item suggests plausibility for early surgery

Heart Lung and Circulation Vol 21, Issues 6-7, June/July 2012

This issue has an Electrophysiology focus.   It includes:

  • historical aspects of device therapy, with Australian perspective
  • MRI and cardiac implantable electronic devices
  • device therapy for brady and tachyarrhythmias
  • device therapy in heart failure
  • electronatomical mapping
  •  ablation in WPW and  AV node re-entry
  • ablation for atrial flutter and other atrial tachycardias
  • ablation for atrial  fibrillation
  • ablation for ventricular arrhythmias
  • ablation in congenital heart disease

 

This is an excellent issue.

Categories: Uncategorized

Journal Club 4 July 2012

Presenter: PM

A randomized open label trial  of use of omega-3 PUFA versus standard care in patients with atrial fibrillation awaiting cardioversion was presented. Details and hyperlink will be posted in due course.