Francesco Pagani

Left atrial isolation associated with mitral valve operations

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent mitral valve operations. From May 1989 to September 1991, 62 patients underwent mitral valve operations (group I); 19, mitral valve operations and DeVega tricuspid annuloplasty (group II); 15, mitral and aortic operations (group III); and 4, mitral and aortic operations and DeVega tricuspid annuloplasty (group IV). Left atrial isolation was performed, prolonging the usual left paraseptal atriotomy toward the left fibrous trigone anteriorly and the posteromedial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesions were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 patients (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (group I, 80.7%; group II, 68.5%; group III, 86.7%; group IV, 75%; p = not significant). Three late deaths (3.1%) were registered. Long-term results show persistence of sinus rhythm in 71% of group I, 61.2% of group II, 85.8% of group III, and 100% of group IV. The unique risk factor for late recurrence of atrial fibrillation was found to be preoperative atrial fibrillation longer than 6 months. Due to the satisfactory success rate in recovering sinus rhythm, we suggest performing left atrial isolation in patients with chronic atrial fibrillation undergoing valvular operations.

Surgical treatment of Wolff-Parkinson-White syndrome: Epicardial approach without the use of cardiopulmonary bypass

Abstract Epicardial dissection without the use of cardiopulmonary bypass (CPB) was performed in 88 patients (56 males and 32 females, mean age 31.9 years). With intraoperative epicardial mapping, 101 accessory pathways were detected, with multiple pathways in 11 patients. CPB was avoided in all but one patient due to frequent onset of atrial fibrillation with rapid ventricular rate. Surgical ablation was successful in 86 patients (97.6%). Three patients required multiple surgical procedures because of persistence of conduction along a component of the original pathway. All but two patients were discharged without antiarrhythmic medication; these two patients were given quinidine therapy because of atrial fibrillation, but had normal early and late electrophysiological studies. Surgical ablation of Kent bundles by the epicardial approach for the treatment of Wolff‐Parkinson‐White syndrome can be achieved without the use of CPB. Optimal and steady exposure of the area are mandatory for the procedure, and dissection is eased by avoidance of heparin required for CPB.

Results with the Novacor assist system and evaluation of long-term assistance.

OBJECTIVE The great number of patients awaiting heart transplant and the shortage of donors has led to the increasing use of left ventricular assist devices (LVAD) for those patients that cannot wait only on medical therapy. In this study we analyze our experience in order to evaluate the possibility of long-term assistance. METHODS We have implanted LVAD Novacor in 36 patients with a mean age of 50.4 years. They were all critical candidates for transplant on high doses of inotrops. We evaluated the clinical and hemodynamic results and studied statistically the relative risk of complications at different time intervals of support. RESULTS In all cases we had a statistically significant improvement of: cardiac output, wedge pressure, pulmonary vascular resistance and mean pulmonary pressure. Eleven patients died on the device, 23 underwent heart transplant and two are still on the device. Causes of death were mostly related to cerebrovascular events or multiorgan failure. Seven of the 23 patients who underwent heart transplant died with a survival rate after transplant of 69.5% and an overall survival rate of 50%. Complications occurred in 33 patients with: 24 strokes, eight TIAs, four cerebral hemorrhages, three peripheral embolisms, seven cable infections, two pocket infections, two sepsis, two major lung infections, one mediastinitis, one right ventricular failure and three multiorgan failure. Time-related analysis showed that these complications occurred mostly during the first 3 months of assistance and this is particularly true for cerebrovascular events. The incidence of infections remained constant during the follow-up period. With a mean time of assistance of 203.1 days we had only two cases of device malfunction at 662 and 1297 days. CONCLUSIONS LVAD Novacor has provided reliable mechanical performance and good hemodynamic improvement. Most complications seem to occur in the first 90 days, therefore long-term assistance could be considered. A reduction of the high rate of thromboembolic complications remains mandatory to improve the clinical results.

Minimally Invasive Approach for Complex Cardiac Surgery Procedures

BACKGROUND A minimally invasive approach through an upper ministernotomy (UMS) has been used in our Division since 1997. On the basis of favorable outcome we have gradually extended this approach from isolated aortic valve replacement (AVR) to more complex cardiac surgery procedures and it is currently our first choice for a variety of procedures. Here we report our 11 years experience. METHODS From 1997 to December 2007, 1,126 procedures were performed at our department, using UMS. Isolated procedures on the aortic valve were performed in 695 patients (61%). Isolated procedures on the aortic valve as redo operation were performed in 77 patients (7%). Complex cardiac surgery procedures (including double valve replacement-repair, ascending aorta-aortic arch replacement, aortic root replacement, aortic dissection, AVR combined with coronary surgery, and complex redo procedures) were performed in 354 patients (32%). Early postoperative outcome was evaluated considering three different groups according to the surgical procedure (first time AVR, redo AVR, and complex procedure). RESULTS Overall conversion to full sternotomy was required in 16 patients (1.4%) with no significant differences between isolated AVR (9 patients, 1.3%) and complex or redo procedures (1 patient [1.2%] and 6 patients [1.6%], respectively). Forty-seven patients died in hospital (cumulative in-hospital mortality of 4.1 %). Mortality according to the procedure was 6.7, 3.8, and 2.8% for complex, redo AVR, or isolated AVR procedures, respectively, with a significant difference only for the complex procedures. Similarly, early postoperative outcome in terms of incidence of prolonged mechanical ventilation and ICU stay was significantly different only in the complex procedure group. Incidence of surgical revision (5.1, 2.9, and 2.7% for complex, redo, or isolated AVR procedures, respectively) showed no statistically significant differences regardless the type of procedures. CONCLUSIONS Our experience clearly shows that a minimally invasive approach through upper ministernotomy is feasible and safe not only for isolated AVR but that it can also be utilized for a variety of complex surgical procedures. Minimizing surgical access may be helpful in patients undergoing complex surgical procedures, especially redo procedures, without compromising the surgical result.

Surgical treatment for ectopic atrial tachycardia

Atrial tachycardia is an infrequent but potentially dangerous arrhythmia which often determines cardiac enlargement. Surgical ablation of the arrhythmia is effective and safe, provided a careful atrial mapping is performed and the surgical technique is tailored to the individual focus location. Eight patients underwent surgical ablation of ectopic atrial tachycardia between 1977 and 1990. Different techniques were adopted for each patient according to the anatomical location of the focus and possibly associated arrhythmias. Whenever possible, a closed heart procedure was chosen. In 1 patient a double focal origin was found and treated by separate procedures. In 1 patient with ostium secundum atrial septal defect and atrial flutter, surgical isolation of the right appendage and the ectopic focus was performed. In all patients ectopic atrial tachycardia was ablated with maintenance of the sinoatrial and atrioventricular nodal function as well as internodal conduction. In follow-up up to December 1991, no recurrency was recorded.

Staged discharge out of hospital of the Novacor left ventricular assist system (LVAS) recipients

The mobility afforded by the wearable Novacor LVAS provides the possibility for the recipients to leave the hospital, with undoubted improvements in their quality of life. A staged program for discharging LVAS recipients from the hospital has been set up at the Policlinico San Matteo of Pavia together with the Rehabilitation Center of Montescano and Baxter Novacor Service support, in order to proceed smoothly towards patients self sufficiency and to minimize any associated risk. The steps are: stay in the hospital ward, discharge to Rehabilitation Center and discharge to home. Several excursions with and without an LVAS team member are encouraged before final discharge to home. Simple criteria of eligibility must be fulfilled to move to the next step. Every move towards a reduced presence of specialized personnel includes an appropriate training of the patient and relatives and a technical checkout of the needed equipment. During the stay at the Rehabilitation Center primarily the physical training and psychological preparation are taken care of by means of tailored programs. When the patient is discharged to home, the check of patient condition is performed weekly at the Rehab Center, bloodwork and technical evaluation is assessed once every two weeks and technical inspections at home twice per year. Complications are reported as in hospital protocol. Control parameters of the LVAS are reported only in case of alarms or abnormal operation. Periodic review of patient training is performed during the check visits, mostly focused on how to address emergency situations. The hospital is responsible for providing one LVAS operator available on call (all hours). Up to date, 11 patients received an implant of LVAS, 9 of them with the wearable system. All of these 9 patients made excursions out of the hospital and 4 patients have successfully undergone the staged program, showing a satisfactory general condition and restoration to social life.

Initial results of clinical trial with a new left ventricular assist device (LVAD) providing synchronous pulsatile flow.

Objectives A multicentric European Clinical Study is ongoing to evaluate safety and efficacy of a new pulsatile implantable LVAD (BestBeat), smaller and lighter than similar devices, capable of providing synchronous and counterpulsating flow with respect to the LV of end-stage heart failure patients. Preliminary clinical results are reported. Methods The new BestBeat LVAD was used, consisting of an implantable pulsatile blood pump, electromechanically driven by a ball screw mechanism, and a wearable electronic controller and power sources. The clinical trial was conducted at 5 European centers. Adult patients affected by CHF in NYHA Class IV despite optimized medical treatment were enrolled. The primary study endpoint was survival at 90 days. Further study endpoints were maintenance of adequate LVAD pump flow and a minimum rate of adverse events during support. Results As of June 2008, 6 patients received the implant. Cumulative support time was 3.7 years, median support time 176 days. All patients who completed the study survived except for one, who died after 48 days, due to combined infection and cerebrovascular accident. Another two patients died: one from intracranial bleeding 113 days after implant, and one from septic shock after 123 days. Hemodynamic improvement with Cl>2.0 l/min/m2 and recovery of end-organ function expressed by consistent improvement of BUN, creatinine and bilirubin were reached in all patients. No device failure was observed. There was no bleeding requiring re-exploration, no hemolysis and only two device-related infections (both in one patient). Neurologic events were reported, the most serious ones occurring in patients with pre-implant respiratory and kidney failure. Three patients were discharged home. Two patients were successfully transplanted, one after 6 months and one after 13 months on device. Conclusions Good performance and efficacy of the device were observed; the endpoints of the study were achieved, and its safety was consistent with expectations. The ongoing study will allow further conclusions to be drawn.

The Pathologic Basis of Recovery

More patients with end-stage heart failure are now being supported by left ventricular assist devices (LVAD) as a bridge to heart transplant. The LVAD unloads the failing heart and modifies the myocardial structure, with regression of left ventricular hypertrophy. The regression of hypertrophy has been reported histomorphologically in paired samples of myocardial tissues obtained from the same patient at the time of LVAD implantation and the heart excised at transplant. The understanding of the mechanisms of recovery may contribute to strategic development for LVAD weaning and the use of LVAD as a destination therapy.

Novacor left ventricular assist device inflow valve endocarditis

A 42-year-old male underwent Novacor left ventricular assist device. Readmitted after 11 months for fever and dyspnea, corynebacterium was isolated and treated with ampicillin and gentamicin for 6 weeks. Transplanted after 388 days on support, device inspection showed one leaflet of the porcine inflow valve perforated by endocarditis process (Fig. 1). www.elsevier.com/locate/ejcts European Journal of Cardio-thoracic Surgery 35 (2009) 910

Left ventricular assistance with Novacor device: the “Pavia Experience”

The shortage of donors is responsible for the majority of patients dying while awaiting transplantation. To rescue these critically ill patients, a wide variety of devices has been proposed for circulatory assistance as bridge to heart transplantation (1,2). The necessity of long periods of bridging because of donor scarcity and because of the need to allow the recovery of the patient before transplantation, has led to the consolidation of left ventricular assistance with electrically-powered devices (4). The wearable system of the Novacor device is the result of the effort to miniaturize the previous large external console. It can be now worn on a belt, allowing high degree of mobility and good quality of life during the waiting period (5). For this reason its use has spread to a large number of transplantation centers and the duration of the assistance has increased significantly over time. In some centers under assistance have been discharged and followed-up as outpatients, thus decreasing the economical impact of circulatory assistance on health care resources.