Longitudinal myocardial contraction improves early during titration with metoprolol CR/XL in patients with heart failure

Treatment of Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a growing epidemiologic problem affecting more than half of the patients with heart failure (HF). HFpEF has a significant morbidity and mortality and so far no treatment has been clearly demonstrated to improve the outcomes in HFpEF, in contrast to the efficacy of treatment in heart failure with reduced ejection fraction (HFrEF).The failure of proven beneficial drugs in HFrEF to influence the outcome of patients with HFpEF could be related to the heterogeneity of the disease, its various phenotypes and multifactorial pathophysiology, incompletely elucidated yet. The diagnosis of HFpEF could be demanding or even inaccurate. Moreover, the therapeutic strategies were influenced by different cut-offs used to define preserved ejection fraction (EF). From this perspective, the current guidelines have classified HFpEF by an EF ≥ 50%, together with a distinct entity, heart failure with mid-range ejection fraction (HFmrEF), defined by an EF ranging from 41-49%.New therapies have been developed to interfere with the mediator pathways of HFpEF at the cellular and molecular level, including mineralocorticoid receptor antagonists, soluble guanylate cyclase stimulators, or angiotensin receptor-neprilysin inhibitors. A number of antidiabetic drugs, such as sodium/glucose cotransporter 2 inhibitors and dipeptidyl peptidase-4 inhibitors are promising options, being under research in large clinical trials. Until the results of ongoing trials shed light on these therapies, guidelines recommend empirical treatment for established HFpEF, and emphasize the crucial role of addressing cardiovascular comorbidities leading to HFpEF, in particular arterial hypertension.

Usefulness of carvedilol to abolish myocardial postsystolic shortening in patients with idiopathic dilated cardiomyopathy

Postsystolic shortening (PSS), a positive myocardial velocity after aortic valve closure as assessed by Doppler tissue imaging, is a common pathologic finding in patients with myocardial disease. Beta-blocker therapy can improve global and regional myocardial function. The aim of the present study was to examine whether the beta-blocker carvedilol might reduce the incidence and magnitude of PSS in patients with idiopathic dilated cardiomyopathy. Before and 2 months after carvedilol therapy, 19 patients (7 men, 12 women; mean age 59 +/- 13 years) underwent conventional echocardiographic assessment and Doppler tissue imaging. Time-velocity curves were constructed at the 12 basal and mid myocardial segments of the left ventricular (LV) walls. PSS was defined if positive myocardial velocity after aortic valve closure was greater than the ejection peak. The number of segments showing PSS was assessed before and after carvedilol therapy. Carvedilol decreased LV end-diastolic dimension (from 66 +/- 5 to 62 +/- 7 mm, p <0.01), increased the LV ejection fraction (from 28 +/- 9% to 36 +/- 8%, p <0.01), and increased early diastolic mitral annular velocity (Ea) (from 5.0 +/- 1.6 to 5.5 +/- 1.7 cm/ms, p <0.01). This was associated with significant reductions in the number of segments showing PSS (from 2.8 +/- 3.0 to 0.8 +/- 1.4, p <0.01). There was a correlation between changes in the number of segments showing PSS and changes in Ea (r = -0.56, p = 0.01). In conclusion, PSS may reflect the severity of LV diastolic function during pharmacologic reverse remodeling in patients with idiopathic dilated cardiomyopathy. These data provide new insights into the mechanisms by which carvedilol improves cardiac function and symptoms in these patients.

Benefit of warm water immersion on biventricular function in patients with chronic heart failure

Background

Regular physical activity and exercise are well-known cardiovascular protective factors. Many elderly patients with heart failure find it difficult to exercise on land, and hydrotherapy (training in warm water) could be a more appropriate form of exercise for such patients. However, concerns have been raised about its safety.

The aim of this study was to investigate, with echocardiography and Doppler, the acute effect of warm water immersion (WWI) and effect of 8 weeks of hydrotherapy on biventricular function, volumes and systemic vascular resistance. A secondary aim was to observe the effect of hydrotherapy on brain natriuretic peptide (BNP).

Methods

Eighteen patients [age 69 ± 8 years, left ventricular ejection fraction 31 ± 9%, _peakVO₂ 14.6 ± 4.5 mL/kg/min] were examined with echocardiography on land and in warm water (34°C).

Twelve of these patients completed 8 weeks of control period followed by 8 weeks of hydrotherapy twice weekly.

Results

During acute WWI, cardiac output increased from 3.1 ± 0.8 to 4.2 ± 0.9 L/min, LV tissue velocity time integral from 1.2 ± 0.4 to 1.7 ± 0.5 cm and right ventricular tissue velocity time integral from 1.6 ± 0.6 to 2.5 ± 0.8 cm (land vs WWI, p < 0.0001, respectively). Heart rate decreased from 73 ± 12 to 66 ± 11 bpm (p < 0.0001), mean arterial pressure from 92 ± 14 to 86 ± 16 mmHg (p < 0.01), and systemic vascular resistance from 31 ± 7 to 22 ± 5 resistant units (p < 0.0001).

There was no change in the cardiovascular response or BNP after 8 weeks of hydrotherapy.

Conclusion

Hydrotherapy was well tolerated by all patients. The main observed cardiac effect during acute WWI was a reduction in heart rate, which, together with a decrease in afterload, resulted in increases in systolic and diastolic biventricular function. Although 8 weeks of hydrotherapy did not improve cardiac function, our data support the concept that exercise in warm water is an acceptable regime for patients with heart failure.

Early impairment of left ventricular long-axis systolic function demonstrated by reduced atrioventricular plane displacement in patients with Marfan syndrome

AIMS

Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 (FBN1) gene. It has been observed that FBN1 deficient mice have reduced left ventricular (LV) systolic function which is correlated to increased transforming growth factor-beta activity. This study aimed to ascertain LV functional abnormalities in MFS patients using M-mode and tissue Doppler imaging (TDI).

METHODS AND RESULTS

In 66 (15-58 years) MFS patients and 61 normal controls, ejection fraction (EF) was evaluated by Simpson's biplane method. Atrioventricular plane displacement (AVPD) obtained from five mitral annular regions was also assessed using M-mode and TDI techniques. To overcome limitations associated with conventional M-mode echocardiography, anatomical and colour anatomical M-mode were also utilized. Ejection fraction was significantly reduced in MFS patients when compared to controls (66.3 +/- 0.74 vs. 71.9 +/- 0.56, P < 0.001), although it was within the normal range. M-mode and TDI AVPD measurements obtained from lateral, septal, inferior, anterior and posterior mitral annular regions were also significantly reduced in MFS patients in comparison to controls (P <0.001, for all measurements).

CONCLUSION

Left ventricular long-axis systolic function is significantly reduced in MFS patients. This data suggests that LV function should be monitored in MFS and appropriate treatment applied if necessary.

The function of left ventricular basal segments is most important for long-term recovery

Adrenergic beta-blockade is the most potent pharmacological therapy for the improvement of global left ventricular (LV) function in heart failure. A substantial portion of patients responds poorly to beta-blockers, but there is scarce information about LV regional function and recovery. We intended to evaluate the effects of beta-blockade on LV regional function and recovery, contractile reserve (CR) and response to long-term treatment.

METHODS

Twenty-two patients with heart failure were investigated at rest and during dobutamine stress echocardiography (DSE), before and after 6 months of metoprolol treatment. LV function was evaluated by global ejection fraction (EF), and by regional function in basal, mid and apical segments.

RESULTS

Recovery of LV global function (increase in EF >5%) after metoprolol treatment was significantly and best correlated to CR in basal segments of the ventricle (r=0.79, p<0.001), in comparison with function of mid and apical segments. The correlation between global recovery and global CR was r=0.55, p=0.007. In a multivariate logistic regression, including global and regional CR, age, gender, etiology of heart failure, ACE-inhibitor treatment, heart rate, and baseline EF, only basal CR was independently associated with recovery, OR 1.07 [95% CI, 1.01-1.21], p=0.019.

CONCLUSION

The strongest association for prediction of LV recovery after metoprolol treatment was found regarding function of basal segments of the ventricle. Patients that responded favourably to beta-blockade had a significantly better CR, and treatment effect, in these segments. This gives further evidence for the importance of myocardial function in basal segments to the contribution of recovery and LV global function.

Pronounced improvement in systolic and diastolic ventricular long axis function after treatment with metoprolol

BACKGROUND

Although it is well known that left ventricular (LV) function improves after treatment with beta-blockers in heart failure, little attention has been paid to the effects on LV long axis (LAX) function.

AIMS

To evaluate LV LAX function after treatment with metoprolol, and to assess whether LV LAX contractile reserve could predict future long-term improvement.

METHODS

Twenty-four heart failure patients were randomised to metoprolol or placebo for 6 months, followed by 6 months of open treatment with metoprolol. Rest and dobutamine stress echocardiography (DSE) was performed before and after each treatment period.

RESULTS

After treatment with metoprolol, LV LAX function improved significantly, systolic velocity from 29+/-8 to 32+/-15 mm/s, p<0.01 (metoprolol) vs. 28+/-7 to 28+/-11 mm/s, ns (placebo); atrioventricular plane fractional shortening (AVP-FS) from 5.4+/-2.1 to 7.4+/-2.7%, p<0.001 (metoprolol) vs. 5.9+/-2.1 to 5.8+/-2.9%, ns (placebo). The improvement in function was maintained during DSE. LV LAX contractile reserve could not predict treatment response; the treatment effect on LV LAX function was significantly greater than the contractile reserve at baseline. The relative improvement in LV LAX function after metoprolol was 38%, compared with a 20% improvement in LV ejection fraction (EF).

CONCLUSION

A significant improvement in LV LAX function was observed after treatment with metoprolol. AVP-FS and systolic velocities increased significantly, and to a greater extent than LVEF.

Circumferential Versus Longitudinal Systolic Function in Patients with Hypertension: A Nonlinear Relation

BACKGROUND

Depressed circumferential midwall performance and impaired left ventricular (LV) longitudinal function are both early markers of LV systolic dysfunction in patients with hypertension. The relation between midwall and longitudinal indices in these patients has never been analyzed.

METHODS

In 126 patients with hypertension, midwall fractional shortening (mFS), stress-corrected mFS, M-mode left atrioventricular plane displacement, and tissue Doppler-derived peak mitral annular systolic velocity were determined.

RESULTS

Regression analysis showed that the relations of midwall indices to atrioventricular plane displacement and mitral annular systolic velocity were all nonlinear. Reductions in atrioventricular plane displacement or mitral annular systolic velocity within their higher ranges corresponded to relatively smaller decreases in mFS and stress-corrected mFS. Relative wall thickness was the strongest determinant of the relative efficiency of circumferential and longitudinal LV contraction.

CONCLUSION

The relation between circumferential midwall and longitudinal function in patients with hypertension is nonlinear and dependent on LV geometry. In these patients, systolic impairment occurs earlier in longitudinal than circumferential performance.

Abnormal regional left ventricular mechanics in treated hypertensive patients with ‘normal left ventricular function’

Global systolic and diastolic LV function assessed by conventional echocardiographic indices is often normal in patients with controlled hypertension, with or without left ventricular hypertrophy. However, it is not certain whether regional myocardial function in these patients remains normal. We investigated 26 patients and 10 age matched normal controls, by means of long axis M-mode echocardiography. There was no significant difference in age, sex distribution, heart rate, blood pressure and routine ECG measurements between the two groups. Although there was significant LVH in patients compared to normal controls, LV cavity size and global systolic function, assessed by shortening fraction, ejection fraction and mean velocity of circumferential fibre shortening did not differ between the two groups, nor did LV diastolic function, assessed by the mitral flow pattern. However, LV regional mechanics, as assessed by multiple long axis M-mode echocardiograms differed significantly, in both systole and diastole, between the two groups. Compared to controls, the total longitudinal systolic excursion in both LV free wall and ventricular septum were significantly reduced in patients, and so was maximum early relaxation and atrial contraction in the LV free wall. The mean rate of systolic excursion in all 3 sites did not differ between the two groups, but the mean rate of early relaxation in both LV free wall and ventricular septum was significantly decreased in patients compared to normal controls. In conclusion, the evaluation of LV dysfunction in patients who have achieved good blood pressure control requires more than a conventional echocardiographic assessment. The assessment of regional mechanics described in the present paper offers an easy and sensitive method for the detection of subtle signs of LV mechanical inefficiency associated with LVH.

Effect of carvedilol on diastolic function in patients with diastolic heart failure and preserved systolic function. Results of the Swedish Doppler-echocardiographic study (SWEDIC)

AIM

The purpose of this study was to investigate the effects of carvedilol on diastolic function (DF) in heart failure patients with preserved left ventricular (LV) systolic function and abnormal DF.

PATIENTS AND METHODS

We randomised 113 patients with diastolic heart failure (DHF) (symptomatic, with normal systolic LV function and abnormal DF) into a double blind multi-centre study. The patients received either carvedilol or matching placebo in addition to conventional treatment. After uptitration, treatment was continued for 6 months. Two-dimensional and Doppler echocardiography were used for quantification of LV function at baseline and at follow-up. Four different DF variables were evaluated by Doppler echocardiography: mitral flow E:A ratio, deceleration time (DT), isovolumic relaxation time (IVRT) and the ratio of systolic/diastolic pulmonary venous flow velocity (pv-S/D). Primary endpoint was change in the integrated quantitative assessment of all four variables during the study.

RESULTS

Ninety-seven patients completed the study. A mitral flow pattern reflecting a relaxation abnormality was recorded in 95 patients. There was no effect on the primary endpoint, although a trend towards a better effect in carvedilol treated patients was noticed in patients with heart rates above 71 beats per minute. At the end of the study, there was a statistically significant improvement in E:A ratio in patients treated with carvedilol (0.72 to 0.83) vs. placebo (0.71 to 0.76), P<0.05.

CONCLUSIONS

Treatment with carvedilol resulted in a significant improvement in E:A ratio in patients with heart failure due to a LV relaxation abnormality. E:A ratio was found to be the most useful variable to identify diastolic dysfunction in this patient population. This effect was observed particularly in patients with higher heart rates at baseline.