Biomedical subjects

B Dahlof

Publications and source records attributed to B Dahlof.

4 recordsLinked to original sources

PubMed1999

Relations of diastolic left ventricular filling to systolic chamber and myocardial contractility in hypertensive patients with left ventricular hypertrophy (The PRESERVE Study).

Abnormalities of left ventricular (LV) diastolic filling and stress-corrected midwall shortening (MWS) have been described in hypertensive patients with normal ejection fraction (EF). However, whether stress-corrected MWS parallels LV diastolic filling better than EF does remains uncertain. Blood pressure, body mass index, echocardiographic LV mass and LV geometry, EF and stress-corrected MWS, LV diastolic filling (peak E- and A-wave velocities, E-wave deceleration time, and atrial filling fraction) were evaluated in 212 hypertensive patients with LV hypertrophy enrolled in the Prospective Randomized Enalapril Study Evaluating Regression of Ventricular Enlargement study. LV structure, geometry, as well as LV diastolic filling, were compared between patients with reduced EF (<55%, n = 39, 18%) and those with normal EF (>55%) as well as between patients with reduced stress-corrected MWS (<89.2%, n = 31, 15%) and those with normal stress-corrected MWS (>89.2%). Patients with reduced EF had higher LV mass, eccentric LV geometry, and higher heart rate than those with normal EF, although they did not differ in age, blood pressure, or body mass index. LV filling pattern was also similar in those 2 groups. Patients with reduced stress-corrected MWS had higher atrial filling fraction, body mass index, heart rate, LV mass, and concentric geometry than those with normal stress-corrected MWS. Atrial filling fraction was negatively associated with stress-corrected MWS, but not with EF in multivariate models, independently of age, gender, heart rate, and body mass index. Thus, in hypertensive patients with LV hypertrophy, abnormal LV diastolic filling is more closely related to impaired myocardial contractility than to LV chamber EF.

Aged↗

PubMed1996

Comparison of enalapril versus nifedipine to decrease left ventricular hypertrophy in systemic hypertension (the PRESERVE trial).

The PRESERVE (Prospective Randomized Enalapril Study Evaluating Regression of Ventricular Enlargement) study is designed to provide a definitive test of the ability of enalapril to achieve greater left ventricular (LV) mass reduction than nifedipine GITs (gastrointestinal treatment system) by a degree that would be prognostically meaningful on a population basis (10 g/m2). To achieve this goal, an ethnically diverse population of 480 men and women with essential hypertension and increased LV mass of screening echocardiography will be enrolled at clinical centers on 4 continents and studied by echocardiography at baseline and after 6 and 12 months' randomized therapy. Blinded readings of echocardiograms at a central laboratory will provide systematic information about treatment effects on LV structure, wall motion, and Doppler blood flow. The study power is at least 90% to test the primary hypotheses that enalapril will induce greater normalization of LV mass and diastolic filling than nifedipine. After the 1-year echocardiographic trial, the study population will be followed 3 more years to test the hypothesis that a reduction in LV mass, independent of blood pressure lowering, is associated with a reduction in the risk of morbid and fatal cardiovascular events.

Antihypertensive Agents↗

PubMed1994

Criteria for an informative trial of left ventricular hypertrophy regression.

Although many studies have been made of hypertensive left ventricular (LV) hypertrophy regression, most have been marred by small numbers of subjects, unrepresentative populations, short study duration, lack of comparison between agents, unblinded echocardiographic readings and inappropriate statistical methods. Meta-analysis and critical reviews of this flawed literature suggest, but do not prove, that some antihypertensive drug classes may reverse LV hypertrophy more effectively than others. Eagerly awaited multicentre trials have not provided definitive answers because of pre-emptive success of concomitant nonpharmacological therapy in reversing both hypertension and LV hypertrophy or excessive drop-out of study participants. Future studies that avoid the above limitations are needed to address three sets of questions: relatively small ones (n > or = 40 to 60) to investigate pathophysiology in detail or explore the effects of new agents; medium-sized ones (n > or = 300-400, time > or = 1 year) to determine definitively whether inter-agent differences in reduction of LV mass exist; and large long-term trials (n > or = 1200, time > or = 4 years) to determine whether LV hypertrophy reversal improves prognosis over and above blood pressure reduction and the type of treatment used.

Clinical Trials as Topic↗

PubMed1987

Antihypertensive effect of a new dihydropyridine calcium antagonist, PN 200-110 (isradipine), combined with pindolol.

Preliminary results of a randomized, double-blind, placebo-controlled trial of PN 200-110 (isradipine) are reported. The study involves 5 centers and 61 patients with essential hypertension. Either PN 200-110 or placebo was added to an ongoing daily regimen of 10 mg of pindolol to determine if this agent would enhance the effect of the beta-adrenoreceptor blocking agent. PN 200-110 was given twice daily, starting with a dose of 2.5 mg or 5 mg, which could be doubled after 4 weeks. The average final dose was 6.3 mg given twice daily. Supine blood pressure was significantly reduced from a mean of 162/103 mm Hg to 144/88 mm Hg (p less than 0.001) in the patients who received the combination therapy. Heart rate did not change significantly. In 3 patients therapy was withdrawn, 1 during placebo and 2 during active treatment, owing to definite or suspected side effects.

Adult↗