El proceso inmediato por la comisión del delito de omisión a la

Ideally, a cut-off value should be identified indicating how much viable myocardium needs to be present to result in response to CRT. Accordingly, ROC curve analysis was performed to identify this cut-off value. As can be observed from Figure 3A, a small amount of viable myocardium was very sensitive for prediction of response to CRT, but at the cost of a low specificity. Conversely, when a larger number of viable segments is present, a substantial increase in specificity is noted, with a drop in sensitivity however. The optimal cut-off value was identified at 11 (65% in a 17-segment model) viable segments; this value yielded a sensitivity of 74% with a specificity of 87%. Moreover, having a total scar score of more than 14 appeared to predictive for non-response (sensitivity 83%, specificity 74%) (Figures 3C and D). These cut- off values need further testing in prospective, larger studies in patients undergoing CRT.

CONCLUSION

The presence of myocardial viability is directly related to response to CRT in patients with ischemic cardiomyopathy. A cut-off value of ≥11 viable segments on FDG imaging yielded a sensitivity and specificity of 74% and 87% respectively to predict response to CRT.

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C h a p t e r 5

Impact of viability and scar