Background Despite hemodynamic optimization, ventricular arrhythmias following left ventricular assist device (LVAD) may persist. We present a case in which transthoracic echocardiogram (TTE) paired with LVAD waveform analysis at time of ventricular arrhythmias assisted in differential diagnosis for the precipitating etiology and helped guide management decisions. Case A 78-year-old African American male with stage D heart failure due to ischemic cardiomyopathy underwent implantation of a HeartWare LVAD. Post-operatively, the patient was weaned off inotropes and pressors with gradual speed adjusted to 2600 rpm over the course of a week. Following optimization, he had several episodes of ventricular tachycardia and ventricular fibrillation requiring defibrillation. The likely etiology of trigger was from a fascicular based premature ventricular contraction or suck down event from speed optimization. Intracardiac hemodynamics with Swan-Ganz catheter revealed normal filling pressures, cardiac index and pulmonary vascular resistance with low suspicion for right ventricular failure. An echocardiogram was without evidence of cardiac tamponade. Furthermore, at the time of TTE, another ventricular arrhythmia was captured (Figure 1). The inflow cannula was visualized to be well-positioned and there was no suction event, despite the ongoing arrhythmia. The left ventricle was not excessively decompressed either with an LVIDD at 4.9 cm with speed increased to 2700 rpm. HeartWare waveforms were visualized real-time without evidence of speed drops or alarms. The patient remained hemodynamically stable with a mean arterial pressure of 78 mmHg. He was successfully managed with metoprolol and sotalol. Conclusion Real-time waveforms on LVAD paired with a TTE can aide in the management in patients with ventricular arrhythmias. As this case demonstrates, not all ventricular arrhythmias merit a reduction in speed, particularly in those patients with normal pulmonary vascular resistance. Despite hemodynamic optimization, ventricular arrhythmias following left ventricular assist device (LVAD) may persist. We present a case in which transthoracic echocardiogram (TTE) paired with LVAD waveform analysis at time of ventricular arrhythmias assisted in differential diagnosis for the precipitating etiology and helped guide management decisions. A 78-year-old African American male with stage D heart failure due to ischemic cardiomyopathy underwent implantation of a HeartWare LVAD. Post-operatively, the patient was weaned off inotropes and pressors with gradual speed adjusted to 2600 rpm over the course of a week. Following optimization, he had several episodes of ventricular tachycardia and ventricular fibrillation requiring defibrillation. The likely etiology of trigger was from a fascicular based premature ventricular contraction or suck down event from speed optimization. Intracardiac hemodynamics with Swan-Ganz catheter revealed normal filling pressures, cardiac index and pulmonary vascular resistance with low suspicion for right ventricular failure. An echocardiogram was without evidence of cardiac tamponade. Furthermore, at the time of TTE, another ventricular arrhythmia was captured (Figure 1). The inflow cannula was visualized to be well-positioned and there was no suction event, despite the ongoing arrhythmia. The left ventricle was not excessively decompressed either with an LVIDD at 4.9 cm with speed increased to 2700 rpm. HeartWare waveforms were visualized real-time without evidence of speed drops or alarms. The patient remained hemodynamically stable with a mean arterial pressure of 78 mmHg. He was successfully managed with metoprolol and sotalol. Real-time waveforms on LVAD paired with a TTE can aide in the management in patients with ventricular arrhythmias. As this case demonstrates, not all ventricular arrhythmias merit a reduction in speed, particularly in those patients with normal pulmonary vascular resistance.