Search PubMed⌕ Search

Biomedical subjects

J L Vacek

Publications and source records attributed to J L Vacek.

At least 73 records · Page 4Linked to original sources

Peripheral vascular disease. Treatment with balloon angioplasty.

Peripheral vascular disease imposes daily inconveniences and limitations on many patients. The primary care physician and vascular specialist can work together to alleviate the restrictions of this disorder by prompt recognition, investigation, and therapy. It is no longer necessary to wait until patients are extremely debilitated before offering intervention. Initial success rates of percutaneous transluminal (balloon) angioplasty are very high and increasing, and restenosis rates are acceptable and decreasing. The procedure is economical and has a short convalescent period and low patient risk. Physicians should be aware that underuse of medical technology may be as costly as overuse. In upcoming years, further advances will allow even more patients with peripheral vascular disease to be treated with lesser expense; lower risk; and greater salvage of lives, limbs, and life-styles.

Activities of Daily Living↗

Nonexercise cardiac stress testing.

Many patients who require evaluation for coronary artery disease are unable to undergo exercise stress testing because of physiologic or psychological limitations. Drs Vacek and Baldwin describe three alternative methods for assessment of cardiac function in these patients, all of which have high levels of diagnostic sensitivity and specificity.

Catecholamines↗

Exercise-induced alterations of signal-averaged electrocardiograms in marathon runners.

Late potentials have been shown to predict malignant ventricular arrhythmias and sudden cardiac death. To determine whether prolonged, strenuous activity is associated with the development of ventricular late potentials, signal-averaged electrocardiography was performed on 30 marathon runners before, immediately after, and during a recovery period at least 1 week after they had a 26.2-mile race. The filtered QRS duration decreased immediately after the marathon to 94.4 +/- 10.0 msec from baseline values of 97.3 +/- 10.1 msec (p less than 0.005). Root mean square energy in the terminal 40 msec of the QRS complex increased immediately after the race from 60.4 +/- 35.6 uV to 71.0 +/- 41.7 uV (P less than 0.5). The duration of signals less than 40 uV in the terminal QRS were not appreciably altered. At the 1-week follow-up study, all parameters closely approximated the baseline values. No runner had a late potential after running the race. The one runner with a late potential at baseline had normal parameters immediately after the race. We conclude that signal-averaged ECG parameters are improved after a marathon is run, and the risk of an arrhythmic sudden death in adult runners without organic heart disease would seem to be low.

Adult↗

Short-term effects of omega-3 fatty acids on exercise stress test parameters, angina and lipoproteins.

The short-term effects of omega-3 fatty acids on exercise test parameters in patients with known coronary artery disease are poorly defined. Therefore, we administered a preparation containing 5.4 g of eicosapentaenoic acid and 3.6 g docosahexaenoic acid to 8 patients in a random order, double-blind, crossover design. The patients were given either fish oil or a vegetable oil control for 6 wk and then crossed over to the other treatment for a second 6-wk period, after a 2-wk wash-out interval. Exercise test parameters, angina frequency, and lipoprotein composition were measured at baseline and at the end of each trial phase. No significant changes were found in resting or peak exercise heart rate or double product, exercise duration or ischemic electrocardiographic changes at peak exercise. Angina frequency and sublingual nitroglycerin usage did not change during either the fish oil or the control oil phase. Plasma triglyceride levels decreased significantly with fish oil treatment and HDL cholesterol levels rose slightly. Total and LDL cholesterol levels were unchanged. We conclude that relatively high dose, short-term administration of omega-3 fatty acids does not alter exercise test parameters.

Adult↗

St. Anthony's fire: a medieval disease in modern times: case history.

Ergot intoxication is a syndrome recognized in the Middle Ages that was due to the effects of intense vasoconstriction upon the extremities. The authors present a patient with self-induced ergotamine poisoning who presented with vasospasm of the right lower extremity and had historical evidence suggestive of vasoconstriction involving other vascular systems. Excess ergot effect should be considered in the differential diagnosis of vascular insufficiency.

Drug Overdose↗

Hemodynamic effects of dopexamine hydrochloride infusions of 48 to 72 hours' duration for severe congestive heart failure.

Dopexamine hydrochloride, a new dopaminergic derivative with potent beta 2-agonist activity, was administered to 10 patients with severe congestive heart failure. Initially, the drug was infused at increasing dosage to achieve a maximal tolerated dose and then titrated to maintain acceptable clinical parameters over the next 48 to 72 hours. Cardiac index increased significantly during the initial titration and at peak effect. Tolerance over the duration of the study was noted in most patients, although further increases in cardiac index could usually be achieved by modest increases in the infusion rate. The peak hemodynamic effect was noted at an average infusion rate of 4.8 micrograms/kg/min. Both stroke volume and stroke work indexes increased during dopexamine hydrochloride infusion in association with decreases in mean arterial, right atrial, mean pulmonary artery and pulmonary capillary wedge pressures, systemic vascular resistance and pulmonary arteriolar resistance. Cardiac output increased by 60% during the infusion and this was out of proportion to the 12% increase in heart rate at peak effect. Most of the increase in cardiac index appeared to be due to the strong vasodilatory profile of the medication producing afterload reduction, with direct inotropic and chronotropic effects contributing to a lesser degree. Drug-related side effects occurred in 4 patients and were easily controlled by down-titration. Dopexamine hydrochloride is an effective and well-tolerated sympathomimetic agent that increases cardiac index while promoting vasodilatation.

Adult↗

Use of a balloon-tipped catheter to guide placement of the bioptome sheath in right ventricular percutaneous endomyocardial biopsy.

A common problem during biopsy of the right ventricular septum using the flexible King's bioptome is the difficulty of accurately directing the tip of the long biopsy sheath against the septal surface. This can be important in that inadvertent biopsy of the more delicate ventricular free wall may lead to perforation and pericardial tamponade. An alternate method of sheath placement is presented. This involves the use of a No. 5 or 6 French balloon-tipped catheter within the long bioptome sheath in order to facilitate sheath passage and positioning. Catheter positioning is readily accomplished when documented by bioplane fluoroscopy, with alternate or additional two-dimensional echocardiographic position check as desired. Balloon-guided positioning for right ventricular septal biopsy appears to be a simple and safe technique that may be especially useful for relatively inexperienced operators and for patients with abnormal cardiac anatomy for whom endomyocardial biopsy (EMB) might normally be technically difficult.

Biopsy↗

Myocardial infarction in the young. Angiographic features and risk factor analysis of patients with myocardial infarction at or before the age of 35 years.

We reviewed the records of 2,400 consecutive patients undergoing cardiac catheterization at USAF Medical Center Keesler between 1978 and 1984 and found 35 patients (1.5 percent of all cardiac catheterizations) aged 35 years or less (mean age, 32 years) who underwent cardiac catheterization after myocardial infarction. These 35 patients (group 1) were compared to a randomly selected group of 100 patients (group 2) aged 55 years or greater who underwent cardiac catheterization for evaluation of coronary artery disease during the same period. The two groups were compared in terms of angiographic features and risk factors for coronary artery disease. The patients in group 1 had a higher proportion of normal coronary arteries (14 percent [5 patients] vs 0; p less than 0.01) and single-vessel disease compared to group 2, while the incidence of three-vessel disease was much less (14 percent [5] vs 47 percent; p less than 0.001). Involvement of the left main coronary artery was uncommon in group 1 (3 percent [1] vs 15 percent in group 2; p less than 0.01). Risk factor analysis revealed smoking to be the most common risk factor in both groups (89 percent [31] in group 1 and 91 percent in group 2). Hypertension (28 percent [10] vs 48 percent; p less than 0.05) and diabetes (3 percent [1] vs 23 percent; p less than 0.01) were more common in group 2. Importantly, of 19 patients in group 1 who underwent cardiac catheterization for prognosis despite being asymptomatic and able to reach at least stage 4 on a Bruce protocol exercise test, none was found to have residual surgically correctable disease.

Adult↗

A review of pericarditis. 1. Causes, manifestations, and diagnostic techniques.

Pericardial disease has many causes, clinical manifestations, and complications. Pericarditis, the most common disease of the pericardium, is classified as acute, subacute, or chronic. Acute pericarditis is characterized by chest pain, dyspnea, and presence of a pericardial friction rub. Patients with chronic pericarditis are generally asymptomatic. Laboratory techniques such as electrocardiography, echocardiography, angiography, radionuclide ventriculography, and computed tomography are useful as primary or adjunctive diagnostic procedures.

Cardiac Tamponade↗

A review of pericarditis. 2. Specific pericardial disorders.

Pericardial disease encompasses a wide range of etiologies and manifestations, the most common of which have been described. Treatments include use of drug therapy, surgical drainage, pericardiectomy, and pericardiotomy. In most cases, treatment is effective.

Drainage↗

Right heart pseudotumor simulated by ascitic pseudocyst. An unusual complication of peritoneovenous shunting.

Peritoneovenous shunting (PVS) for intractable ascites has an extensive clinical experience, with several well-described complications. We recently noted an unusual complication of PVS with a Denver shunt. A 37-year-old woman who had placement of a shunt for chylous ascites 18 months prior to presentation demonstrated on a large, mobile mass filling the right atrium which, during atrial systole, partially prolapsed into the right ventricle. At cardiac surgery, a 4 X 10 cm mass with attachment to the tip of the shunt was found. Intracardiac ascitic pseudocyst is a potentially lethal complication of PVS with the Denver shunt which should be considered with a high index of suspicion and evaluated with echocardiography.

Adult↗

Metastatic malignant melanoma presenting clinically as obstruction of the right ventricular inflow and outflow tracts. Characterization by magnetic resonance imaging.

Metastatic disease involving the heart may present in a variety of fashions. A patient with melanoma metastatic to the right ventricle which was diagnosed clinically by evidence of recent onset of right ventricular inflow and outflow tract obstruction is described. Important information regarding the extent of the metastatic process and potential resectability of the tumor was gained by magnetic resonance imaging.

Cardiomegaly↗