Biomedical subjects

Volkmar Falk

Publications and source records attributed to Volkmar Falk.

58 records · Page 4Linked to original sources

PubMed2002

Curative treatment of atrial fibrillation with intraoperative radiofrequency ablation: short-term and midterm results.

OBJECTIVE: This report describes the early and midterm results after intraoperative radiofrequency ablation of atrial fibrillation for patients with isolated chronic atrial fibrillation or atrial fibrillation in combination with additional valvular and nonvalvular cardiac diseases. METHODS: From August 1998 to March 2001, a total of 234 patients with chronic atrial fibrillation underwent isolated intraoperative radiofrequency ablation alone (n = 74, 31.6%) or in combination with other cardiac procedures, such as mitral valve reconstruction (n = 57, 24.4%), mitral valve replacement (n = 38, 16.2%), aortic valve replacement (n = 11, 5.1%), coronary artery bypass grafting (n = 8, 5.0%), or a combination of the last with other cardiac procedures (n = 46, 19.7%). In all cases anatomic reentrant circuits confined within the left atrium were eliminated by placing contiguous lesion lines involving the mitral anulus and the orifices of the pulmonary veins through the use of radiofrequency energy application (exposure time, 20 seconds). A median sternotomy was used in 101 cases (43.2%), and video assistance through a right lateral minithoracotomy was used in 133 cases (56.8%). RESULTS: A total of 188 patients (83.9%) were discharged in sinus rhythm, 17 patients (7.6%) had atrial fibrillation, and 19 patients (8.5%) had atypical flutter. Pacemakers were implanted in 23 patients (9.8%). There were 10 in-hospital deaths (4.2%), and 30-day mortality was 5 patients (2.1%). In 3 cases (1.3%) an atrioesophageal fistula developed, necessitating surgical repair. Six months' follow-up was complete for 122 (61.0%) of 200 patients, with 99 patients still in stable sinus rhythm (81.1%, 95% confidence interval 73.1%-89.9%). Twelve months' follow-up was complete for 80 (90.9%) of 88 patients, with 58 patients still in sinus rhythm (72.5%, 95% confidence interval 61.3%-83.2%). CONCLUSIONS: Intraoperative radiofrequency ablation is a curative procedure for chronic atrial fibrillation. It is technically less challenging than the maze procedure and can be applied through a minimally invasive approach. Protection of the esophagus seems mandatory to avoid the deleterious complication of a left atrioesophageal fistula, such as was observed in 3 cases.

Adult↗

PubMed2002

Five years of less invasive mitral valve surgery: from experimental to routine approach.

BACKGROUND: In the last five years, mitral valve surgery has changed fundamentally. This study reviews our experience in less invasive mitral valve surgery (LIMS) during that time. METHODS: LIMS was performed in 449 patients (age 59 +/- 14 years, 237 female) via a right lateral minithoracotomy. The operations included 42 "redo" procedures. After initially experiencing a high number of complications, we have modified and simplified the procedure. After using the Port- Access? Technique (PAT) in the earlier stages of our series, in the last 226 patients the aorta was clamped directly using the transthoracic clamping (Chitwood) technique (TTC). In our most recent cases, PAT was only employed in redo procedures. In 336 patients, the procedure was completed with robotic assistance, and in 23 of these we used the da Vinci telemanipulation system. RESULTS: The mitral valve was repaired in 327 patients and replaced in 122 patients. In 100 patients, additional surgical procedures (TVR n = 13, ASD closure n = 16, left atrial ablation n = 65, left atrial reduction plasty n = 6) were performed. Bypass and clamp time, including times for both additional and redo procedures, were 124 +/- 44 min. and 65 +/- 29 min. in the overall series. Complications, which were mainly neurological, were fewer in the TTC group than in the PAT group (n = 4 vs. n = 17; p <0.04). Hospital mortality was 3.1% and 5.2%, respectively, for the two groups. There were no additional costs associated with using the TTC technique compared to conventional procedures. Mean survival rate was 96.3% at a mean follow-up of 727 +/- 451 days (95% CI, 677 to 779). CONCLUSIONS: Less invasive mitral valve surgery enables the patient to avoid the surgical trauma associated with sternotomy. It has developed into a reliable technique with reproducible results for primary, redo, and additional procedures. LIMS has become the standard approach for mitral valve operations at our institution.

Cardiac Surgical Procedures↗

PubMedDate not supplied

Temporary extracorporeal membrane oxygenation in patients with refractory postoperative cardiogenic shock--a single center experience.

BACKGROUND: Approximately 1% of patients require temporary circulatory support due to refractory cardiogenic shock following cardiac surgery. Such patients are at very high risk for subsequent morbidity and mortality. We evaluated the results of temporary extracorporeal membrane oxygenation (ECMO) support in patients with postcardiotomy cardiogenic shock. METHODS: From November 1997 to February 2000, 7900 patients underwent cardiac surgery in our institution. Ninety-five patients (1.2%) (CABG, n = 63; AVR, n = 16; CABG and AVR, n = 8; other procedures, n = 8) required temporary postoperative ECMO support. ECMO implantation was performed via the femoral vessels or via the right atrium and ascending aorta. Intraaortic balloon counterpulsation was employed in all patients. RESULTS: Mean duration of ECMO support was 2.8 +/- 2.1 days. Forty-five patients (47%) were successfully weaned from ECMO. Of these, 28 patients were discharged from hospital 35.8 +/- 20.8 days post-ECMO support. Overall hospital mortality for all ECMO patients was considerable at 71%. Mortality rate in the combined CABG and AVR group was 100% (P < 0.05 versus the other surgical groups). ECMO support was complicated by renal failure in 64% of patients, bleeding requiring mediastinal reexploration in 62%, ischemia of the lower limbs in 16%, cerebral edema in 6%, and cerebral hemorrhage in 3%. CONCLUSIONS: ECMO is a suitable technique for short-term treatment of refractory postoperative low cardiac output. Mortality rates are comparable to other cardiac assist devices, with approximately 30% of patients able to be discharged from hospital.

Aged↗

PubMedDate not supplied

Swan-Ganz catheter-induced severe complications in cardiac surgery: right ventricular perforation, knotting, and rupture of a pulmonary artery.

BACKGROUND: The role of Swan-Ganz catheterization for cardiac surgery and perioperative management has recently been scrutinized. METHODS: Prospective observational study for serious complications related to Swan-Ganz catheterization. 7150 patients undergoing cardiac operations at a major European heart center and academic setting. 3730 Swan-Ganz catheter placements for cardiac surgery (7.5 French Swan-Ganz Catheter Baxter, heparin coated). RESULTS: We observed four serious complications related to Swan-Ganz catheterization and placement (0.1%): A right ventricular free wall perforation occurred, one trouble with knotting, and two pulmonary artery ruptures. The right ventricular perforation was controlled with a suture, the knot was tightened, and the catheter withdrawn through insertion. The first case of pulmonary artery rupture was treated conservatively. All of these patients survived. The other pulmonary artery rupture occurred during coronary artery bypass grafting. Emergency lobectomy was performed. This patient died due to bleeding during the early postoperative course. CONCLUSION: The incidence of serious Swan-Ganz catheter complications in our patient population is comparable to the incidence reported in the literature. Based on these results the use of Swan-Ganz catheters in cardiac surgery is still justified since the rate of associated serious complications is extremely low. Despite the rare occurrence of serious complications and the infrequent fatal outcomes, the benefit of its use in selected cases of cardiac surgery overweight its associated complications.

Aged, 80 and over↗