Pseudo-false-positive exercise treadmill testing caused by systolic anterior motion of the anterior mitral valve leaflet.

Subendocardial ischemia as indicated by electrocardiography during exercise, in association with severe systolic anterior motion of the anterior mitral valve leaflet without left ventricular hypertrophy, has not been well described. We report the case of a 42-year-old man who presented with symptoms of exertional angina and 2-mm ST depression on treadmill electrocardiography but had a normal perfusion scan and coronary angiogram. Initially the negative angiographic results caused us to regard the treadmill results as false-positive. Subsequently, low-dose dobutamine echocardiography showed severe systolic anterior motion of the anterior mitral valve leaflet with a >144-mmHg left ventricular outflow tract gradient; we then recognized the original treadmill results to be pseudo-false-positive. Electrocardiographic changes in association with the above-described motion of the anterior mitral valve leaflet and increased left ventricular outflow tract gradient were verified by use of treadmill and supine bicycle stress echocardiography.

Diagnosis and management of inadvertently placed pacing and ICD leads in the left ventricle: a multicenter experience and review of the literature.

Three patients from different centers with pacemaker or ICD leads endocardially implanted in the left ventricle are described. All leads, two ventricular pacing leads and one ICD lead, were inserted through a patent foramen ovale or an atrial septum defect. The diagnosis was made 9 months, 14 months, and 16 years, respectively, after implantation. All patients had right bundle branch block configuration during ventricular pacing. Chest X ray was suggestive of a left-sided positioned lead except in the ICD patient. Diagnosis was confirmed with echocardiography in all patients. One patient with a ventricular pacing lead presented with a transient ischemic attack at 1-month postimplantation. During surgical repair of the atrial septum defect 14 months later, the lead was extracted and thrombus was attached to the lead despite therapy with aspirin. The other patients were asymptomatic without anticoagulation (9 months and 16 years after implant). No thrombus was present on the ICD lead at the time of the cardiac transplantation in one patient. We reviewed 27 patients with permanent leads described in the literature. Ten patients experienced thromboembolic complications, including three of ten patients on antiplatelet therapy. The lead was removed in six patients, anticoagulation with warfarin was effective for secondary prevention in the four remaining patients. In the asymptomatic patients, the lead was removed in five patients. In the remaining patients, 1 patient was on warfarin, 2 were on antiplatelet therapy, and in 3 patients the medication was unknown. After malposition was diagnosed, three additional patients were treated with warfarin. In conclusion, if timely removal of a malpositioned lead in the left ventricle is not preformed, lifelong anticoagulation with warfarin can be recommended as the first choice therapy and lead extraction reserved in case of failure or during concomitant surgery.

Long-term prognosis in women with normal dobutamine stress echocardiography.

Although the long-term prognosis for patients with a normal dobutamine stress echocardiographic result is good, most studies have focused on men. We assessed the long-term cardiac prognosis for women by reviewing the cases of 100 women who underwent dobutamine stress echocardiography for suspected coronary artery disease and found that women with a normal result have an excellent long-term cardiac prognosis.

Congestive heart failure arising from diastolic dysfunction in the presence of normal left-ventricular systolic function.

Congestive heart failure due to diastolic dysfunction is a common clinical entity, particularly in the elderly. As outlined, such patients fall into a larger group of all patients with CHF symptoms and normal systolic function. When finding "normal" systolic function, the clinician should embark upon a carefully outlined diagnostic work-up geared toward eliminating confounding or treatable contributing causes of dyspnea or typical CHF symptoms. The prognosis for CHF patients with primarily diastolic dysfunction is not as poor as for those with LV systolic dysfunction, although the prevalence, associated morbidity, and costs are great. In contrast to the large number of successful clinical trials that have guided treatment of LV systolic failure, an extremely limited number of trials have specifically addressed themselves to diastolic dysfunction. Marked symptomatic relief can often be provided with careful attention to tailored therapy, although little is known with regard to outcome. Refinements in noninvasive imaging methods and hemodynamic indices of diastolic function may lead to improved patient care.

Thrombolytics and left-sided prosthetic valve thrombosis. A case report.

Prosthetic valve thrombosis is a well-known condition. Because surgical treatment of prosthetic valve thrombosis is associated with a high mortality rate, the use of thrombolysis as therapy for this condition has gained popularity in recent years. In this article, we discuss the cases of 3 patients who presented to our institution with left-sided prosthetic valve thrombosis between 1994 and 1997. All 3 patients presented with New York Heart Association functional class III or IV symptoms, and all were successfully treated with urokinase. The use of thrombolytic therapy for left-sided prosthetic valve thrombosis is associated with low mortality rates, and therefore is an attractive alternative to valve replacement or thrombectomy. However, the risk of embolic and hemorrhagic complications precludes the use of thrombolysis in patients with large thrombi and in those with New York Heart Association functional class I and II symptoms; for these patients, the risk associated with thrombolysis exceeds surgical mortality rates.

Vasopressin mediates the pressor effects of endothelin in the subfornical organ of the rat.

The potent vasoconstrictor peptide endothelin may affect central cardiovascular function in areas with incomplete blood-brain barrier such as the subfornical organ (SFO). In these studies, we determine whether microinjection of endothelin-1 (ET-1) into the SFO increases blood pressure (BP) in a dose-related manner and investigate the potential involvement of sympathetic and vasopressinergic mechanisms. In urethane-anesthetized Sprague-Dawley rats, BP was recorded intra-arterially, and ET-1 (0.125-6.0 pmol/60 nl) was microinjected stereotaxically into the SFO. Whereas vehicle (60 nl) did not change mean BP or HR, ET-1 evoked a dose-related pressor and bradycardic effect. The maximal changes were noted at the 1-pmol dose. No significant hemodynamic effects were observed with ET-1 microinjection in areas immediately surrounding the SFO or into the SFO of rats pretreated with a specific endothelin antagonist. In animals instrumented for recording of renal sympathetic nerve activity (RSNA), the administration of ET-1 (1 pmol/60 nl) evoked pressor (14 +/- 5 mm Hg) and bradycardic (-41 +/- 12 bpm) effects with a decrease in RSNA (16% +/- 3%). The effects on HR and RSNA seem to be mediated by baroreflex changes because in sino-aortic denervated rats, ET-1 pressor effects occur without inhibition of HR or RSNA. We documented the involvement of vasopressin in ET-1 actions by using vasopressin antagonists that inhibited the effects evoked by ET-1 administration. In addition, increases in vasopressin plasma levels were demonstrated at the time of the maximal effect of this peptide. These results indicate that ET-1 acting in the SFO increases BP by a vasopressinergic mechanism.

Effects of halfway house placement on retention of patients in substance abuse aftercare.

One hundred twenty-four male veterans were enrolled in the Birmingham VAMC Outpatient Substance Abuse Clinic (OSAC) aftercare program following inpatient treatment for alcohol, cocaine, or mixed alcohol-cocaine abuse/dependence. Forty-two of the patients were concurrently admitted to a nearby halfway house (HH) while the remaining 82 patients made community-based (CB) living arrangements. Chi-square analysis showed the two groups were matched, p > .05, in regard to age, race, marital status, presenting problem, and referral source. The CB group experienced significantly, p < .05, higher early dropout (40 vs 0%) from aftercare. Of the others engaging in treatment, the HH patients stayed in OSAC aftercare 60 days longer and had significantly, p < .01, more clinic visits. A higher proportion, p < .01, of HH patients completed each of four treatment milestones: education group, psychological testing, psychological interview, and treatment planning/update. On average, the HH patients remained in OSAC an additional 90 days after their halfway house discharge. Although not significantly different, p > .05, the frequency of HH patients receiving administrative discharge status of Treatment Complete was twice (28.2%) that of CB patients (15.1%). It is concluded that concurrent halfway house placement can aid in aftercare retention and completion.

Transesophageal echocardiography predicts mortality in critically ill patients with unexplained hypotension.

OBJECTIVES: This study sought to determine the prognostic yield and utility of transesophageal echocardiography in critically ill patients with unexplained hypotension. BACKGROUND: Transesophageal echocardiography is increasingly utilized in the intensive care setting and is particularly suited for the evaluation of hypotension; however, the prognostic yield of transesophageal echocardiography in these patients is unknown. METHODS: We prospectively studied 61 adult patients in the intensive care unit with sustained (> 60 min) unexplained hypotension. Both transthoracic and transesophageal echocardiography were performed, and results were immediately disclosed to the primary physician, who reported any resulting changes in management. Patients were classified on the basis of transesophageal echocardiographic findings into one of three prognostic groups: 1) nonventricular (valvular, pericardial) cardiac limitation to cardiac output; 2) ventricular failure; and 3) noncardiac systemic disease (hypovolemia or low systemic vascular resistance, or both). Primary end points were death or discharge from the intensive care unit. RESULTS: A transesophageal echocardiographic diagnosis of nonventricular limitation to cardiac output was associated with improved survival to discharge from the intensive care unit (81%) versus a diagnosis of ventricular disease (41%) or hypovolemia/low systemic vascular resistance (44%, p = 0.03). Twenty-nine (64%) of 45 transthoracic echocardiographic studies were inadequate compared with 2 (3%) of 61 transesophageal echocardiographic studies (p < 0.001). Transesophageal echocardiography contributed new clinically significant diagnoses (not seen with transthoracic echocardiography) in 17 patients (28%), leading to operation in 12 (20%). CONCLUSIONS: Transesophageal echocardiography makes a clinically important contribution to the diagnosis and management of unexplained hypotension and predicts prognosis in the critical care setting.

Cardiovascular effects of endothelin injected into brain nuclei regulating vasopressin release.

We studied the cardiovascular effects produced by administration of endothelin-1 (ET-1) into brain nucleic known to affect vasopressin release. In urethane-anesthetized Sprague-Dawley rats, microinjection of ET-1 into the subfornical organ (SFO) resulted in a dose-dependent increase in arterial blood pressure and a decrease in heart rate. These effects were inhibited by previous administration of the ETA receptor antagonist BQ-123 or by intravenous administration of a vasopressin antagonist. In addition, microinjection of ET-1 into the SFO increased plasma levels of vasopressin. In contrast, in the paraventricular nucleus (PVN) of the hypothalamus microinjection of ET-1 evoked a dose-related bradycardia with inconsistent changes in blood pressure. Although the bradycardia was antagonized by intra-PVN administration of BQ-123, the vasopressin antagonist did not affect the changes in heart rate evoked by microinjection of this peptide into the PVN. Overall, these results indicate that the central cardiovascular effects of ET-1 result from activation of several mechanisms, including stimulation of brain centers regulating vasopressin release.

Identifying effective components of alcohol abuse prevention programs: effects of fear appeals, message style, and source expertise.

Despite the importance of alcohol abuse prevention programs, the effectiveness of many components of these programs has not been demonstrated empirically. An experiment tested the efficacy of three components of many prevention programs: fear appeals, one- versus two-sided message style, and the expertise of the source. The persuasive impact of this information was examined on 113 ninth-grade students' intentions to abstain from drinking alcohol while they are teenagers. The results reveal that fear appeals are successful in strengthening students' intentions to refrain from drinking. Implications are discussed for implementing these principles and for designing future investigations of alcohol abuse prevention programs.