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Maryl R Johnson

Publications and source records attributed to Maryl R Johnson.

5 recordsLinked to original sources

Relation between contractile reserve and improvement in left ventricular function with beta-blocker therapy in patients with heart failure secondary to ischemic or idiopathic dilated cardiomyopathy.

Beta blockers improve left ventricular (LV) ejection fraction but patient responses are heterogenous. We investigated the role of contractile reserve (CR) in predicting beta-blocker response in ischemic and nonischemic cardiomyopathy. Resting and low-dose dobutamine echocardiograms were recorded in 32 patients with heart failure (LV ejection fraction <or=35%), 18 with ischemic cardiomyopathy (IC), and 14 with idiopathic dilated cardiomyopathy (IDC). A segment was defined as CR positive (CR+) or negative (CR-) based on response to dobutamine. Patients were then classified as CR+ or CR- based on number of improved segments (IC group) or ejection fraction improvement (IDC group) in response to dobutamine. During follow-up (2, 6, and 14 months after beta-blocker initiation), response was measured by the percent of segments showing improved contractility from baseline, ejection fraction, and wall motion score index. In the IC group, the percent of improved segments was greater at 2 and 6 months in CR+ versus CR- (70% vs 15% and 39% vs 17%, p <0.05), whereas it was greater at all periods in the patients with IDC (36% vs 9% at 2 months, 50% vs 19% at 6 months, and 63% vs 42% at 14 months, p <0.05). Findings for ejection fraction and wall motion score index were similar. Therefore, time course and magnitude of improvement in LV function in patients with heart failure receiving beta blockers are related to CR status. CR predicts a greater early response in IC, whereas it predicts a greater response at all time periods in IDC. However, even patients without CR showed improvement in LV function at 14 months.

Adrenergic beta-Antagonists↗

Gadolinium cardiovascular magnetic resonance predicts reversible myocardial dysfunction and remodeling in patients with heart failure undergoing beta-blocker therapy.

BACKGROUND: In some patients with heart failure, beta-blockers can improve left ventricular (LV) function and reduce morbidity and mortality. We hypothesized that gadolinium-enhanced cardiovascular magnetic resonance imaging (CMR) can predict reversible myocardial dysfunction and remodeling in heart failure patients treated with beta-blockers. METHODS AND RESULTS: Forty-five patients with chronic heart failure underwent CMR. Contrast imaging using gadolinium was performed to obtain high-resolution spatial maps of myocardial scarring and viability. Cine imaging was performed to assess LV function and morphology and was repeated in 35 patients after 6 months of beta-blockade. Gadolinium CMR demonstrated scarring in 30 of 45 patients (67%). Scarring was found in 100% of patients with ischemic cardiomyopathy (28 of 28) but in only 12% with nonischemic cardiomyopathy (2 of 17). In the 35 patients who were maintained on beta-blockers and had a second study, there was an inverse relation between the extent of scarring at baseline and the likelihood of contractile improvement 6 months later (P<0.001). For instance, contractility improved in 56% (674 of 1207) of regions with no scarring but in only 3% with >75% scarring (8 of 232). Multivariate analysis showed that the amount of dysfunctional but viable myocardium by CMR was an independent predictor of the change in ejection fraction (P=0.01), mean wall motion score (P=0.0007), LV end-diastolic volume index (P=0.007), and LV end-systolic volume index (P< or =0.0001). CONCLUSIONS: For heart failure patients treated with beta-blockers, gadolinium-enhanced CMR predicts the response in LV function and remodeling.

Adrenergic beta-Antagonists↗

Is heart failure survival improving? Evidence from 2323 elderly patients hospitalized between 1989-2000.

BACKGROUND: While drug therapy and medical management improved markedly over the last decade, the basic clinical characteristics of the heart failure patient population treated at the study hospital changed little. This offers an excellent opportunity to study potential heart failure survival improvements for a general patient population. METHODS: Vital status follow-up through 2001 was obtained from the Social Security Death Index for all 2323 patients aged >or=65 years at the time of an initial, medically managed heart failure hospitalization between October 1989 and March 2000. Kaplan Meier survival probabilities were compared across 4 time periods in the 1990s. A Cox proportional hazards model was used to estimate age, sex, race and comorbidity-adjusted differences in survival among patients admitted in 1989-1991 and 3 subsequent multi-year periods. RESULTS: There was an increase in the proportion of older female patients with more chronic conditions. Compared with patients admitted in 1989-1991, survival probabilities for patients admitted in 1999-2000 had improved about 5% at 30 days (to 95%) and 10% at 1 year in 1999-2001 (to 73.5%). For those admitted between 1989-1998, there was a 9% improvement over 1989-1991 at 5 years (to 36%). Hazards model results indicated that patients admitted in 1999-2000 had a relative risk of death only 66% that of patients admitted in 1989-1991 (P <.0001). CONCLUSIONS: These findings provide evidence of modest but significant short-term survival improvements, particularly after 1998, when drug therapy had became optimal in the inpatient setting, patient education and discharge planning became better documented, and inpatient mortality rates had declined substantially.

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