PubMed Health⌕ Search

Biomedical subjects

P T Makler

Publications and source records attributed to P T Makler.

At least 19 recordsLinked to original sources

Effects of six-month afterload reduction therapy with hydralazine in chronic aortic regurgitation.

Seventeen patients with chronic asymptomatic aortic regurgitation (AR) were studied to determine whether 6 months of hydralazine therapy can reduce the severity of AR or reverse left ventricular (LV) enlargement and hypertrophy. Echocardiography, radionuclide angiography at rest and during exercise, and maximal treadmill exercise with respiratory gas analysis were performed at intake and after a 6-month double-blind treatment period. After dose titration with hydralazine, patients were randomized to their maximal tolerated hydralazine dose or to placebo. At intake, hydralazine and placebo groups were similar. Six patients taking hydralazine and 8 taking placebo completed the study protocol. One patient taking placebo died and 2 patients taking hydralazine withdrew with drug-related adverse effects. The mean titrated dose of hydralazine was 96 +/- 9 mg, but the mean treatment dose was 63 +/- 21 mg administered 3 times daily because of drug intolerance. After 6 months, mean systolic blood pressure with hydralazine therapy decreased from 136 to 125 mm Hg (p less than 0.02), and end-systolic posterior wall thickness increased from 1.58 to 1.70 cm (p less than 0.05), resulting in a significant reduction in M-mode meridional end-systolic stress (from 104 to 80 kdynes/cm2) (p less than 0.05). M-mode fractional shortening increased from 0.28 to 0.31 (p less than 0.05) with hydralazine, but mean LV echocardiographic dimensions were unchanged. LV mass increased from 383 to 434 g (p less than 0.05) with hydralazine primarily because of an increase in end-diastolic wall thickness. In the placebo group, there was no change in any of the hemodynamic or echocardiographic parameters at 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Effects of age on ventricular performance during graded supine exercise.

To assess the effects of age on ventricular performance, graded supine exercise tests with equilibrium radionuclide ventriculography were performed in six normal subjects of mean age 37 +/- 4 years and in eight normal subjects with a mean age of 59 +/- 2 years. At a standard submaximal work load, older subjects had a similar heart rate (older: 126 +/- 10, younger: 128 +/- 5 bpm) and systolic blood pressure responses (older: 198 +/- 24, younger: 202 +/- 24 mm Hg). Cardiac output counts increased appropriately in both groups during submaximal exercise. However, when expressed as percent change from resting values, the increases in cardiac output (older: 125 +/- 14, younger: 75 +/- 10 L/min; p less than 0.05) were greater for the older subjects. The percent change in end-diastolic counts (older: 8.4 +/- 5, younger: -2.8 +/- 4), stroke counts (older: 26 +/- 6, younger: 8.6 +/- 4), and ejection fraction (older: 18 +/- 3, younger: 11 +/- 1%) in proceeding from rest to exercise Stage III (600 kg-m/min) was greater for the older subjects. Age-related differences in each of these measurements were significant at p less than 0.05. These findings suggest that cardiac output during exercise is maintained by an increased heart rate in younger subjects, and by a combination of increased heart rate and the Frank-Starling mechanism in older individuals. Since the heart rate and mean blood pressure response to exercise were similar in both groups, the use of the Frank-Starling mechanism during exercise in older subjects suggests that age-related differences in ventricular preload are important in modulating the performance of the aging left ventricle.

Adult↗

A false-positive indium-111 labeled leukocyte scintigram in a patient with a painful hip prosthesis.

A Tronzo hip prosthesis is designed to elicit an inflammatory reaction in order to promote prosthesis stability. A three-phased bone scan and Ga-67 imaging in conjunction with physical examination and laboratory findings failed to demonstrate evidence for osteomyelitis in a patient with a painful hip prosthesis, in whom images obtained with In-111-labeled leukocytes were positive. This observation demonstrated that the interpretation of the latter technique in demonstrating inflammation can cause a false impression of an infectious process.

Diagnosis, Differential↗

Visualization of the uterus on evaluation of transplanted kidneys.

A vascular blush was noted in the pelvis during flow studies in two women with kidney transplants. The vascular structure was noted to be due to the uterus. In one patient, the activity in the area of the uterus could have been mistaken for excretion of agent into the bladder.

Diagnostic Errors↗

Accuracy of left ventricular ejection fraction using the nuclear stethoscope in left ventricular aneurysm.

Although the nuclear stethoscope, a nonimaging probe, accurately determines left ventricular (LV) ejection fraction (EF), its reliability in patients with LV aneurysm has not been established. Accordingly, LVEF was determined using the nuclear stethoscope and compared with that determined by equilibrium gated blood pool scanning in 29 patients, 1 studied on 2 separate occasions, for a total of 30 patient studies. Patient studies were separated into 2 groups. Patients in group I (n = 20) had no gated blood pool evidence for aneurysm, and those in group II (n = 10) had discrete focal akinesia or dyskinesia. Nineteen patients (13 in group I and 6 in group II) had 2 separate nuclear stethoscope acquisitions. In group I, EF determined by gated blood pool scanning (53 +/- 4%, mean +/- standard error) did not differ from that determined by nuclear stethoscope (51 +/- 4%). EF determined using either gated blood pool scanning (32 +/- 6%) or nuclear stethoscope (35 +/- 5%) was significantly lower in group II than in group I, although nuclear stethoscope and gated blood pool scanning did not differ. Reproducibility was excellent (r = 0.96). Overall, nuclear stethoscope and gated blood pool EFs correlated closely (r = 0.93), and the correlation coefficients were similar in groups I (r = 0.92) and II (r = 0.92). The slopes of the regression curves for group I (0.97) and group II (0.92) were not statistically different. These results confirm the accuracy and reproducibility of LVEF determination by nuclear stethoscope and specifically demonstrate its reliability in patients with LV aneurysm.

Adult↗

Quantitative analysis of liver function in percutaneous transhepatic biliary drainage patients.

The diagnostic usefulness of Tc-99m DISIDA cholescintigraphy as a predictor of eventual catheter and hepatic function in patients who have undergone percutaneous transhepatic biliary drainage (PTBD) for extrahepatic biliary obstruction was evaluated. Twenty-nine cholescintigrams were performed in 14 patients. The examinations were divided into two groups: Group A (N = 17), in which the patient's clinical status deteriorated within two to three days post-PTBD, and Group B (N = 12), in which the patients did well clinically post-PTBD. No significant difference between the two groups was demonstrated by visual analysis of the analog images or by analysis of serum bilirubin levels. A computer program, developed by the authors, quantitates several parameters of DISIDA kinetics, reflecting hepatic function based upon compartmental analysis. A significant difference (P less than .001) was demonstrated between the mean transport constants (blood clearance constant = k1; hepatic clearance constant = k2) for the two groups. It is concluded that serum bilirubin levels and visual inspection of analog images are inadequate independent predictors of hepatic function in patients post PTBD. The transport constants k1 and k2 are quantitative parameters of hepatic function that may be of prognostic value in patients post PTBD.

Adult↗