Left ventricular size determines tissue Doppler-derived longitudinal strain and strain rate.

AIMS: Tissue Doppler-derived indices of strain (epsilon) and strain rate (SR) have been developed to assess regional cardiac function. However, the effect of left ventricular (LV) size on epsilon and SR has not been studied in depth. The aim of this study was to assess to what extent heart size influence epsilon or SR. METHODS AND RESULTS: In 21 anaesthetized pigs ranging from 12.5 to 70.0 kg, tissue Doppler-derived epsilon and SR, and haemodynamic parameters, were assessed during controlled heart rates and different loading conditions. dP/dt did not correlate to pig weight, suggesting constant contractility during growth. Longitudinal epsilon and SR were significantly higher in smaller compared with larger hearts. The hyperbolic correlation between pigs weight and epsilon and SR was r(2)=0.621 and 0.372, respectively, both P<0.0001. Afterload elevation induced a reduction in longitudinal epsilon (from -24.2+/-3.2 to -12.1+/-5.5%, P=0.001) and SR (from -2.3+/-0.8 to -1.3+/-2.4 s(-1), P=0.034), whereas increasing preload increased epsilon (from -26.4+/-10.3 to -38.1+/-14.3%, P=0.006) and SR (from -2.3+/-0.9 to -4.22+/-1.8 s(-1), P=0.002). CONCLUSION: Longitudinal epsilon and SR decrease with increasing LV dimensions in spite of an unaltered contractility. These results show and confirm that heart size influences epsilon and SR, which are highly load-dependent parameters.

How many acute heart failure patients need a ventricular assist device?

OBJECTIVES: The most severe forms of acute heart failure have a dismal prognosis despite modern invasive treatment. For some of these patients, improved outcome must relay on early institution of ventricular assist devices (VAD). We aimed to estimate the potential VAD need in acute heart failure. DESIGN: All patients admitted to the ICU or CCU for acute heart failure (AHF) in 2003/04 (n=302) were reviewed. Non-survivors with severe acute heart failure, i.e. cardiogenic shock and postcardiotomy HF, were individually reviewed to assess eligibility for VAD-treatment. RESULTS: Cardiogenic shock and postcardiotomy HF was present in 23% (n=69) and 19% (n=57) of the AHF patients. Overall in hospital mortality in these groups was 38% (n=48). Of these, 15 were less than 75 years of age, without serious comorbidities and thus deemed to be potential candidates for VAD-treatment. CONCLUSION: This survey indicates that 12% of patients with severe acute heart failure are potential candidates for VAD-treatment. Extending these figures to a national level, indicate that approximately 70 patients per year could be candidates for short-term VAD-treatment in Norway.

Utilization and outcome of coronary revascularization and valve procedures in acute heart failure--an evaluation based on the classification from the European Society of Cardiology.

Early invasive treatments in patients with acute heart failure (AHF) are critical components to improve outcome. We aimed to establish if such treatments were applied according to existing guidelines and also to assess the subsequent mortality in the complete AHF population. All patients with AHF admitted to the intensive care unit/coronary care unit during the years 2003-2004 (n=302) were retrospectively reviewed and classified according to the European Society of Cardiology. Invasive revascularization was applied more frequently in patients with cardiogenic shock following acute coronary syndromes (78%, n=40) than in less severe AHF (58%, n=62, P<0.05). Only 8% (n=4) of eligible patients with acute coronary syndromes and cardiogenic shock were treated non-invasively. Valvular dysfunction was a precipitating factor for AHF in 15% (n=38). Acute mitral regurgitation was treated surgically exclusively in patients with mechanical defects. In-hospital mortality rates for less severe AHF was 12%, cardiogenic shock 46% and postcardiotomy HF 32%. Invasively treated patients had lower in-hospital mortality in both cardiogenic shock (35% vs. 70%, P=0.006) and less severe AHF (6% vs.17%, P=0.042). The study revealed an appropriate use of invasive revascularization. The high mortality in patients with severe AHF indicates that more effective treatment options are needed in eligible patients.