LV ejection fraction

Ideally biomarkers of activity should be identified at various times over the course of the study to support the pharmacodynamic activity (e.g., normalization of insulin, improvement in beta cell function as measured by C-peptide level, or control of glucose following transplantation of P pancreatic islet cells) improvement of motor coordination in mice with spinal cord damage following transplant of neurons or repair of heart function (e.g., functional measures such as LV ejection fraction, pressure volume loops, ventricular pressure and heart wall thickness). Such markers may also be useful in subsequent clinical... 

Iliceto et al.205 CEDIM L-camitine administration within 24 h and for 12 months in AMI patients 472 LV remodeling, LV ejection fraction Significant reduction in LV dilation, no difference in LV ejection fraction... 

Patients with an anterior MI who require permanent pacing often have a low LV ejection fraction that makes them potential candidates for a prophylactic implantable cardioverter-defibriUator. A recent study in patients who suffered an acute MI suggests waiting 3-6 months before implanting a defibrillator (32). Despite this recommendation, it makes sense to implant a cardioverter-defibrillator (which contains a pacemaker component) in patients who actually require only a permanent pacemaker at that juncture. Such patients are also at risk for sudden death from a ventricular tachyarrhythmia. It makes no sense to wait 3-6 months without protection for bradycardia until a cardioverter-defibrillator can be implanted on the basis of a poor LV ejection fraction according to the DINAMIT trial (32). 

Analysis of patients in many CRT studies has shown that 30-40% of the patients failed to respond to CRT as measured by clinical improvement (NYHA class, hospitalization from heart failure, improved exercise capacity) or more objective echocardiographic parameters (LV ejection fraction, LV volumes, mitral regurgitation) (1,11,13,36). The response to CRT cannot be reliably predicted by currently accepted EKG criteria for implantation (QRS width greater than 120 ms). In fact, many patients with widened QRS complexes do not respond while many who do respond do not show changes in their QRS complex (25). Eigure 11.7 shows the lack of correlation between the QRS duration on EKG and mechanical dyssynchrony evaluated with TDI. 

For candidate selection several factors have to be assessed low left ventricular (LV) ejection fraction, right ventricular dysfunction, the New York Heart Association (NYHA) functional class, ventricular arrhythmias, measurement of functional capacity with determination of maximal oxygen consumption, hemodynamic measurements, pulmonary capillary resistance and the neurohumoral activation resulting from congestive heart failure (elevated plasma norepinephrine levels) (Aaron-SON et al. 1997 Doval et al. 1996 Gradman and Deedwania 1994 MANCiNietal. 1991 Stevenson et al. 1990). 

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