Late tamponade with mechanical circulatory support

Usefulness of HVAD Waveforms as Diagnostic Assistance for Cardiac Tamponade

We experienced a 39-year-old male patient who converted paracorporeal left ventricular assist device to HeartWare ventricular assist device (HVAD; Medtronic, Framingham, MA) as bridge-to-transplant indication. On the 10th postoperative day, the HVAD flow waveform presented periodical low pulsatility pattern. Significant pericardial hematoma was observed on the imaging studies, and he showed pulsus paradoxus. He was highly suspected of cardiac tamponade and performed thoracotomy. HVAD waveform might be a useful tool to monitor and early suspect of postoperative cardiac tamponade to consider more intensive examinations and thoracotomy before hemodynamic deterioration, although further large-scale studies are warranted to strengthen our hypothesis.

Remote monitoring for better management of LVAD patients: the potential benefits of CardioMEMS

Left ventricular assist devices (LVAD) are frequently used in the treatment of end-stage heart failure (HF), and due to the shortage of heart donors and destination programs, it is likely to keep on growing. Still, LVAD therapy is not without complications and morbidity and rehospitalization rates are high. New ways to improve LVAD care both from the side of the patient and the physician are warranted. Remote monitoring could be a tool to tailor treatment in these patients, as no feedback exists at all about patient functioning on top of the static pump parameters. We aim to provide an overview and evaluation of the novel remote monitoring strategies to optimize LVAD management and elaborate on the opportunities of remote hemodynamic monitoring with CardioMEMS, at home in these patients as the next step to improve care.

Minimally invasive approach to thoracic effusions in patients with ventricular assist devices

The aim of this study was to compare our experience between open and video-assisted thoracic surgery (VATS) approaches to the management of thoracic effusions in ventricular assist device (VAD) patients. This was a retrospective review of a prospectively collected database of VAD patients at a single institution. Patients who were operated on for pericardial and/or pleural effusions were included. Primary outcomes included operative mortality and morbidity as well as effusion recurrence. From 1993 to 2009, 360 adult patients underwent VAD placement. Twenty-three patients (11.9%) required operative management of pleural (n = 24), pericardial (n = 13) or both pleural and pericardial (n = 6) effusions [open = 20 (47%); VATS = 23 (53%)]. Drainage with decortication was performed in five patients, with the remaining undergoing drainage alone. Open and VATS patients were similar in age, gender and indication for VAD support. Conversion from VATS to open was necessary in four patients (17%). There was no operative mortality and no difference in perioperative complications between approaches. The open and VATS approaches had similar rates of pleural (open = 63%; VATS = 41%; P = 0.42) and pericardial (open = 31%; VATS = 17%; P = 1) effusion recurrences. In spite of apparent challenges, the VATS approach may be as safe and effective as open surgery for the management of pleural and pericardial effusions in VAD patients in centres with significant minimally invasive thoracic experience.

Perioperative echocardiographic examination for ventricular assist device implantation

Ventricular assist devices (VADs) are systems for mechanical circulatory support of the patient with severe heart failure. Perioperative transesophageal echocardiography is a major component of patient management, and important for surgical and anesthetic decision making. In this review we present the rationale and available data for a comprehensive echocardiographic assessment of patients receiving a VAD. In addition to the standard examination, device-specific pre-, intra-, and postoperative considerations are essential to the echocardiographic evaluation. These include: (a) the pre-VAD insertion examination of the heart and large vessels to exclude significant aortic regurgitation, tricuspid regurgitation, mitral stenosis, patent foramen ovale, or other cardiac abnormality that could lead to right-to-left shunt after left VAD placement, intracardiac thrombi, ventricular scars, pulmonic regurgitation, pulmonary hypertension, pulmonary embolism, and atherosclerotic disease in the ascending aorta; and to assess right ventricular function; and (b) the post-VAD insertion examination of the device and reassessment of the heart and large vessels. The examination of the device aims to confirm completeness of device and heart deairing, cannulas alignment and patency, and competency of device valves using two-dimensional, and color, continuous and pulsed wave Doppler modalities. The goal for the heart examination after implantation should be to exclude aortic regurgitation, or an uncovered right-to-left shunt; and to assess right ventricular function, left ventricular unloading, and the effect of device settings on global heart function. The variety of VAD models with different basic and operation principles requires specific echocardiographic assessment targeted to the characteristics of the implanted device.

Device and patient management in a bridge-to-transplant setting

BACKGROUND

A variety of sophisticated devices have been developed for mechanical circulatory support in patients bridged to cardiac transplantation. Based on 13 years' experience, we have developed specific protocols for patient selection and management for different devices.

METHODS

The principal systems applied in the bridge-to-transplant cohort are the Thoratec ventricular assist device (n = 144, mean duration of support 53 +/- 57 days), the Novacor left ventricular assist system (LVAS) (n = 85, mean duration of support 154 +/- 15 days), and the HeartMate LVAS (n = 54, mean duration of support 143 +/- 142 days). The Thoratec device is used for biventricular assistance or if the duration of support is expected to be less than 6 months. For long-term support, either the Novacor or HeartMate LVAS are preferred.

RESULTS

Despite careful postoperative patient management, this group of patients is prone to a variety of complications. Bleeding occurred in 22% to 35%, right heart failure in 15% to 26%, neurologic disorders in 7% to 28%, infection in 7% to 30%, and liver failure in 11% to 20% of patients. Complications varied with the device applied and the patient's preoperative condition. A total of 73 patients were discharged from hospital for a mean period of 184 days; this cumulative experience amounted to 37.5 patient-years.

CONCLUSIONS

The Novacor and the HeartMate systems offer the additional possibility of discharging patients during support if they fulfill certain criteria. The main reasons for rehospitalization were thromboembolic and infectious complications.

Tamponade after open-heart surgery with percutaneous cardiopulmonary support

A 56-year-old man presented with late cardiac tamponade appearing on 9 postoperative day after weaning from percutaneous cardiopulmonary support. He had been referred to our hospital for congestive heart failure. He underwent aortic valve replacement and fell into postcardiotomy low output syndrome. He could not be weaned from extracorporeal circulation, and we had to use an intraaortic balloon pump and percutaneous cardiopulmonary support. On postoperative day 9, percutaneous cardiopulmonary support was successfully withdrawn without problems, but he showed signs of superior vena cava syndrome after the cannulas were removed. An echocardiogram also showed cardiac tamponade. When the wound was reopened, a lot of old clots had compressed the right atrium and, after clot removal, the patient's hemodynamic state improved markedly. It is important to be aware that percutaneous cardiopulmonary support may conceal hemodynamic deterioration due to cardiac tamponade and to take care that a patient does not experience hemodynamic deterioration after percutaneous cardiopulmonary support withdrawal.