engleski

The Acute Impact of Cardiac Resynchronization Therapy on Left Ventricular Function - The Role of Intraoperative Echocardiography.

BACKGROUND: A 73 year old female patient with dilated cardiomyopathy was admitted to our department for the implantation of a biventricular pacemaker, based on the guidelines criteria (QRS width 160 ms, EF 25%, NYHA III-IV, LBBB, optimal medical therapy). The patient had severe mitral valve regurgitation and a history of prior multiple hospitalizations due to heart failure, with a tendency of worsening of the cardiac status during the past few months, manifesting in severe dispnoea (even on minimal exertion and sleep) and orthopnoea. MATERIALS AND METHODS: An echocardiographic examination (GE, Vivid i), extended with a Doppler myocardial imaging study (DMI), was performed pre-operatively and intra-operatively immediately following the implantation. Images were acquired with both the pacemaker switched off and programmed in bi-ventricular and right atrial stimulation. RESULTS: In pre-operative and intra-operative studies there was important intra-ventricular asynchrony of left ventricular motion, with a marked „ septal-flash“ indicating early septal activation and contraction followed by late lateral contraction, stretching the septum. Without pacing, severe mitral valve regurgitation was present and EDV=219 ml, ESV=138 ml, SV=39 ml. After biventricular pacing, the intra-operative cardiac imaging showed that cardiac motion was more coordinated and the „ septal-flash” was not present anymore. Mitral regurgitation did decrease and cardiac function was improved - EDV=177 ml, ESV=131 ml, SV=63 ml. CONCLUSION: The successful implantation of the biventricular pacing markedly improved cardiac performance. By decreasing the intra-ventricular myocardial dysynchrony, there was a consistent decrease in mitral regurgitation, end-diastolic and end-systolic volume along with an increase in stroke volume, thus improving the overall functional status of the heart. Intra-operative echocardiography, including the acquisition of myocardial velocities, can be used as a tool for a quick and reliable interrogation of bi-ventricular pacing lead placement and response to cardiac resynchronization therapy.

Cardiac Resynchronization Therapy; Left Ventricular Function; Intraoperative Echocardiography.

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