More on Ivabradine in Tachycardia with Paraganglioma

The authors reply:

We agree with Scagliola and Brunelli that the hemodynamic benefits of ivabradine have been reported in multiple studies. However, we would like to note that the patient populations in previously published studies differ from our patient, who never had low cardiac output. Invasive cardiac monitoring was not obtained in our patient, because there were no clinical indications to do so; therefore, many of the variables discussed in the aforementioned studies were not available for our patient. Throughout the course of our patient’s treatment, he was monitored with echocardiography, which revealed a stable stroke volume and cardiac index. Grade I to II diastolic dysfunction was present in our patient, but these changes did not correlate with the use of ivabradine. It is important to consider that our patient had severe hypertension during treatment, which often led to the use of multiple antihypertensive medications, with an inevitable effect on diastolic function. Further studies in large populations of patients appear to be warranted to better delineate the wide spectrum of hemodynamic benefits associated with the use of ivabradine.