The clinical and hemodynamic effects of coenzyme Q10 in congestive cardiomyopathy.

Despite major advances in treatment congestive heart failure (CHF) is still one of the major causes of morbidity and mortality. Coenzyme Q(10) is a naturally occurring substance that has antioxidant and membrane stabilizing properties. Administration of coenzyme Q(10) in conjunction with standard medical therapy has been reported to augment myocardial kinetics, increase cardiac output, elevate the ischemic threshold, and enhance functional capacity in patients with congestive heart failure. The aim of this study was to investigate some of these claims. Seventeen patients (mean New York Heart Association functional class 3.0 +/- 0.4) were enrolled in an open-label study. After 4 months of coenzyme Q ( 10 ) therapy, functional class improved 20% (3.0 +/- 0.4 to 2.4 +/- 0.6, p < 0.001) and there was a 27% improvement in mean CHF score (2.8 +/- 0.4 to 2.2 +/- 0.4, p < 0.001). Percent change in the resting variables included the following: left ventricular ejection fraction (LVEF), +34.8%; cardiac output, +15.7%; stroke volume index, +18.9%; end-diastolic volume area, -8.4%; systolic blood pressure (SBP), -4. 4%; and E (max), (SBP / end-systolic volume index [ESVI]) +11.7%. MVo ( 2 ) decreased by 5.3% (31.9 +/- 2.6 to 30.2 +/- 2.4, p = NS). Therapy with coenzyme Q(10) was associated with a mean 25.4% increase in exercise duration and a 14.3% increase in workload. Percent changes after therapy include the following: exercise LVEF, +24.6%; cardiac output, +19.1%; stroke volume index, +13.2%; heart rate, +6.5%; SBP, -4.3%; SBP / ESVI, +18.6%; end-diastolic volume (EDV) area, -6.0%; MVo (2), -7.0%; and ventricular compliance (%Delta SV / EDV) improved >100%. In summary, coenzyme Q(10) therapy is associated with significant functional, clinical, and hemodynamic improvements within the context of an extremely favorable benefit-to-risk ratio. Coenzyme Q(10) enhances cardiac output by exerting a positive inotropic effect upon the myocardium as well as mild vasodilatation.

First-pass radionuclide cineangiography in diagnosis of coronary artery disease in patients older than 75 years: evaluation of sensitivity.

The sensitivity of first-pass radionuclide cineangiography in the detection of coronary artery disease was evaluated in 60 patients subdivided equally according to age younger than or older than 75 years. The mean age of group 1 (age > or = 75 years) was 80.2 years +/- 5.3, and the mean age in group 2 (age < 75 years) was 62.0 years +/- 6.4. Disease prevalence in group 1 was 87% versus 80% in group 2. Group 1 had higher prevalence of hypertension (67% vs 33%) and lower prevalence of typical angina pectoris (23% vs 55%). Overall sensitivity of first-pass radionuclide cineangiography in group 1 was 93% versus 97% in group 2. Older patients had significantly lower maximal heart rates, workloads, and exercise durations, and age correlations were significant for exercise heart rate, workload, and exercise duration. Failure to achieve an adequate exercise endpoint had significant effect on testing sensitivity only in the younger subjects (98% vs 60%), indicating that sensitivity of first-pass radionuclide cineangiography is age independent.

First-pass radionuclide cineangiography: a reevaluation of its sensitivity and limitations in the detection of significant coronary artery disease.

The sensitivity of first-pass cineangiography in the detection of significant coronary artery disease (CAD) was recently assessed in 33 patients. No normal controls were studied. Overall sensitivity was 86% with a predictive value of 83% and a 36% false-positive rate. Attainment of an adequate exercise end point increased sensitivity to 92%; failure to achieve this end point diminished sensitivity to 71%. Correlation between first-pass and contrast angiography ejection fractions was high (r = 0.88, p less than .005) with a moderate correlation in wall motion analysis (r = 0.58, p less than .005). The development or the intensification of a wall motion abnormality (WMA) was the single most sensitive indicator of CAD (84%). Presence of WMA plus failure of the ejection fraction to increase by 6% over baseline increased testing sensitivity to 89%. The mean WMA score for patients with CAD was 2.0 +/- 1.5 compared with 0.6 +/- 1.3 for those with normal study results (p less than .01). The first-pass method identified 4 subjects who subsequently had normal findings from catheterization. Data confirm testing sensitivity of the first-pass technique and underscore the apparent limitations of this modality in differentiation of patients with normal vasculature.

Outpatient dobutamine therapy: the rhyme and the riddle.

Advances in critical care medicine have increased survival for victims of myocardial infarction and other acute cardiac events so that increasingly patients are receiving long-term, labor-intensive, and costly medical care. Innovations in drug delivery systems and skyrocketing health care costs have fostered the growth of home health care which has blossomed into a $2.8 billion industry. There is evidence that outpatient dobutamine therapy produces definite physical and possibly psychological improvements of variable degree and duration. Hemodynamic improvements are generally associated with improvement in functional class, and the financial savings are recognizably substantial. However, three major problems confront therapies with beta-adrenergic agonists: tendency for tolerance, ventricular arrhythmias, and increased myocardial oxygen consumption. There is a dire need for establishment of exclusionary patient criteria and for risk stratification, as well as for development of a portable radionuclide nonimaging monitor. Given the current fund of knowledge, outpatient dobutamine therapy should be undertaken cautiously after meticulous patient selection reflecting an awareness of the tremendous complexities and inherent risks. The therapeutic implications are dependent on the nature of the underlying cardiomyopathy and the fact that beta-adrenergic receptor desensitization is unlikely to be overcome by progressive dosage increases. Therapy is initiated with the understanding that treatment will remain blindly empirical and conjectural in the absence of a continuous physiologic monitor and an expanded comprehension of the molecular pathophysiology of the failing ventricle.

Relapsing native-valve enterococcal endocarditis: a unique cure with oral ciprofloxacin combination drug therapy.

Enterococcal endocarditis is the third most common presentation in native valves, and it is the most refractory. Unique among the streptococci, enterococci are relatively resistant to beta-lactam antibiotics requiring a combination aminoglycoside regimen for cure. Relapse is common even after apparently adequate therapy and may be seen in up to 25% of cases that involve streptomycin-resistant strains. This problem is magnified by the recent appearance of beta-lactamase-producing strains of S. faecalis resistant to both ampicillin and gentamicin. Ciprofloxacin is being investigated with a number of antimicrobials in the attempt to identify superior protocols against troublesome pathogens. However, little published data is available concerning the clinical efficacy of this drug in enterococcal endocarditis. In vitro studies and preliminary trials with animal models have generally been disappointing with broth macrodilution time-kill or agar dilution proving the most reliable in vitro methods for predicting in vivo outcomes. The urgent need to identify new combination drug regimens is underscored not only by the development of new resistance patterns, but by the well-documented toxicities of conventional therapies. The authors present a case of relapsing enterococcal endocarditis caused by a non-beta-lactamase-producing strain of S. faecalis, which demonstrated high-level resistance to streptomycin but not to gentamicin. Relapses occurred despite favorable laboratory data and aggressive beta-lactam-gentamicin therapies. Cure was achieved using oral ciprofloxacin in a combination drug regimen, which is reported here for the first time.

Hemodynamic benefits of atrial ventricular sequential pacing in complete heart block and left ventricular failure: case study.

The authors describe 2 cases of insertion of atrial ventricular (AV) sequential pacemakers and their hemodynamic benefits.