Surgical treatment of atrial fibrillation : a systematic review

BACKGROUND

The recently published overwhelming number of publications on the surgical treatment of AF, using a wide variety of techniques, blurred any precise appreciation of the nowadays surgical treatment of AF. As a consequence, the "state of the art" of the surgical technique of AF is ill-defined.

OBJECTIVES

In this review the efficacy of the alternative sources of energy (radiofrequency-microwave and cryoablation; (group I) and the classical "cut and sew" Cox-Maze III (group II), which claims a 97-99% sinus rhythm (SR) success rate, were evaluated in the surgical treatment of atrial fibrillation (AF).

METHODS

A computerized search in the PubMed and Medline database was conducted. Only original, English written, clinical manuscripts on the surgical treatment of atrial fibrillation citing the clinical outcome, including the postoperative sinus rhythm, were included. The following data were registered: the absolute numbers and percentages of treated patients, gender (male versus female) distribution, the type of arrhythmia (permanent or paroxysmal AF), type of surgery (mitral or non-mitral valve or a lone AF surgical procedure), postoperative morbidity (bleeding, the use of an intra-aortic balloon pump, cerebral vascular accident), postoperative pacemaker implantations, 30-day mortality, survival and sinus rhythm conversion. The mean values for age (years), left atrial diameter (mm), preoperative duration of AF (years) and left ventricular ejection fraction (%) were also recorded.

RESULTS

Forty-eight studies were included comprising 3832 patients: 2279 in group I and 1553 in group II. The mean duration of AF, left atrial diameter and LVEF were 5.4 versus 5.5 years (p=0.90), 55.5 versus 57.8 mm (p=0.23) and 57 versus 58% (p=0.63). The postoperative SR rates for group I and II were 78.3 versus 84.9% (p=0.03). However, the "cut and sew" Cox-Maze III was conducted in younger patients (55.0 versus 61.2 years; p=0.005), more often to treat paroxysmal (22.9 versus 8.0%) and lone AF (19.3 versus 1.6%). Alternative sources of energy were predominantly used to treat permanent AF (92.0%), almost always as a concomitant surgical procedure (98.4%) and increasingly in combination with non-mitral valve surgery (18.5%). After correction for these variations, the postoperative SR conversion rates for group I and II did not differ significantly anymore.

CONCLUSIONS

We could not identify any significant difference in the postoperative SR conversion rates between the classical 'cut and sew' and the alternative sources of energy, which were used to treat atrial fibrillation.

Sicherheit und Effektivit�t der intraoperativen gek�hlten linearen Hochfrequenzstromablation bei Patienten mit Vorhofflimmern w�hrend eines kardiochirurgischen Eingriffs

METHODS

A total of 113 patients with chronic permanent (104) or paroxysmal (9) atrial fibrillation underwent open heart surgery plus an additional antiarrhythmic procedure using saline-irrigated cooled-tip radiofrequency ablation (SICTRA) for biatrial or left atrial linear lesions. Ablation was performed with steps of short (5 seconds) ablation around the pulmonary vein ostia and interconnecting lines. Postoperative complications and conversions to sinus rhythm were followed up (mean follow-up duration 17+/-14 months).

RESULTS

Of the 113 patients, 16 died during follow-up (day 3 up to 33 months) resulting in a cumulative survival of 79% (2 sudden cardiac deaths, 2 gastrointestinal bleedings, 1 renal bleeding, 2 mediastinitis, 1 endocarditis, 1 hemorrhagic insult, 2 respiratory insufficiencies and 2 unknown). Three patients died between day 3 and 6 (30-day mortality 3%) due to low cardiac output. Complications occurred in 19% of the patients including 4% bleeding, 1% pneumothorax, 3% sternal dehiscence, 3% reversible low cardiac output, 6% reversible respiratory insufficiency, 2% TIAs and 1% intra aortal balloon pump implantation. Conversion to sinus rhythm usually occurred spontaneously within 6 months resulting in a cumulative percentage of 80% in sinus rhythm. In these patients, 85% showed biatrial contraction.

CONCLUSIONS

SICTRA to treat atrial fibrillation can safely and effectively be combined with different surgical procedures. Mortality and complication rates are comparable to cardiac surgery without antiarrhythmic procedures. No severe procedure-related complications were noted when a stepwise ablation approach during open heart surgery was used. Antiarrhythmic surgical procedures are highly effective in restoring sinus rhythm in patients with atrial fibrillation. Is a modified approach using intraoperatively cooled-tip radiofrequency ablation to induce linear lesions safe and effective in the treatment of atrial fibrillation in cardiosurgical patients?

Repair of a postinfarct ventricular septal defect on the beating heart. Surgical considerations

Postinfarct ventricular septal defect (VSD) still remains associated with a high mortality and morbidity. Despite the development of modern surgical techniques and medical care it continues to be a difficult therapeutic challenge. This report describes a case of a 70-year-old female patient, who presented with a postinfarct VSD after having anterior wall infarction. She presented with left heart failure, pulmonary hypertension and left to right shunt of 78% (Qp/Qs=4.3). The patient was operated on using cardiopulmonary bypass on the beating heart. The closure was performed with a Dacron-patch and a single bypass to the diagonal branch using the left internal thoracic artery. Postoperatively the patient did well and was discharged in good condition on the 13th postoperative day. We conclude that postinfarction VSD can be repaired on cardiopulmonary bypass avoiding cross-clamping. This method is helpful for the outcome as well as for the early postoperative recovery of elderly patients.

Efficacy of an additional MAZE procedure using cooled-tip radiofrequency ablation in patients with chronic atrial fibrillation and mitral valve disease. A randomized, prospective trial

AIMS

This study is the first prospective randomized trial evaluating the efficacy of an antiarrhythmic surgical procedure in patients with chronic atrial fibrillation undergoing mitral valve replacement.

METHODS AND RESULTS

Thirty consecutive patients with chronic atrial fibrillation undergoing mitral valve replacement were randomized for an additional modified MAZE-operation using intra-operatively cooled-tip radiofrequency ablation (group A) or mitral valve replacement alone (group B). Biatrial contraction was studied and functional capacity was evaluated in spiro-ergometry 6 months after surgery. Thirty-day mortality was 0% in both groups. After 12 months, sinus rhythm was reinstituted significantly more often in patients of group A (cumulative rate of sinus rhythm 0.800) compared to patients in group B (0.267) (P<0.01). 66.7% of patients in sinus rhythm of group A had documented biatrial contraction. Electrocardioversion showed long-term success in only 17% of patients in group A and 0% in group B. Maximal aerobic uptake at the 6-month spiro-ergometry revealed no significant difference (9.3 vs 8.5 ml x min(-1) kg(-1), P=0.530).

CONCLUSIONS

A modified MAZE operation using cooled-tip radiofrequency ablation can be safely combined with mitral valve surgery and is highly effective in restoring sinus rhythm. Biatrial contraction is found in 66.7% of patients with sinus rhythm undergoing mitral valve replacement plus the MAZE operation.

Saline-irrigated, cooled-tip radiofrequency ablation is an effective technique to perform the maze procedure

BACKGROUND

We evaluated the effectiveness of the saline-irrigated-cooled-tip-radiofrequency ablation (SICTRA) to produce linear intraatrial lesions.

METHODS

Thirty patients with chronic atrial fibrillation and mitral valve disease were consecutively randomized to have mitral valve operation either with a Maze procedure (group A) or without (group B). Intraatrial linear lesions were made with an SICTRA catheter (20 to 32 W; 200 to 320 mL/h saline). An echocardiography and 24-hour electrocardiogram were obtained 12 months postoperatively.

RESULTS

The cumulative frequencies of sinus rhythm in group A and B were 0.80 and 0.27 (p < 0.01). Restored biatrial contraction was present in 66.7% (6 of 9) of the group A patients in sinus rhythm. One patient from each group received a permanent pacemaker because of bradycardia. A fatal renal bleeding and mediastinitis occurred in 2 group A patients, 6 weeks postoperatively. One group A patient had sudden cardiac death at home, 4 months after operation. One patient from each group had lethal respiratory failure, 7 and 10 months after operation. Survival after 12 months for group A and B was 73% and 93% (p = 0.131).

CONCLUSIONS

The SICTRA appeared to be an effective technique to perform the Maze procedure.

Pulmonary function and postoperative complications after wedge and flap reconstructions of the main bronchus

Between 1980 and 1989, 8 wedge and 17 flap main bronchoplasties were done in 24 patients (4 carcinoid tumors, 4 benign lesions, 17 carcinomas). Bronchial anastomotic stenoses, pulmonary function, and survival were evaluated. Preoperative ventilation/perfusion scans with preoperative and postoperative spirometry were done in all patients except two who underwent a wedge bronchoplasty. Postoperative bronchoscopy was done in all patients. Follow-up was complete for the patients with carcinoma (N = 17). In the wedge group bronchial anastomotic stenoses occurred in three (38%) of eight patients. All three patients had serious postoperative complications (persistent atelectasis in one, prolonged ventilatory support in two); one patient died and the other two had impaired postoperative pulmonary function. Complete function recovery occurred in only three (38%) of eight patients who underwent wedge bronchoplasty. In the flap group, bronchostenosis occurred in 3 (18%) of 17 patients. The associated complications (mucus retention, minor atelectasis, partial lobar torsion) were mild. Complete pulmonary function recovery occurred in 13 (76%) of 17 patients who had flap bronchoplasty. Actuarial survival, for the patients with carcinoma, was 88%, 47%, and 41% after 1, 3, and 5 years, respectively. The local recurrence rate was 25% (4/16). In our series, flap main bronchoplasties were effective for the resection of bronchial tumors with local involvement of the adjacent main bronchus. Wedge main bronchoplasties, however, were associated with substantial postoperative complications.

Lung function and perfusion after bronchial and pulmonary arterial sleeve resection

Between January 1985 and December 1991, six patients underwent arterial and bronchial sleeve resections of the left upper lobe. Preoperative and postoperative spirometry, preoperative split pulmonary radionuclide ventilation/perfusion (V/Q) scans and postoperative bronchoscopy were obtained in four patients. Postoperative serial digital vascular images (DVI) of the pulmonary artery were obtained in three patients and one patient had a postoperative V/Q scan. For each patient the preoperative and postoperative forced expiratory volume in is (FEV1) were determined to assess the postoperative ventilatory recovery. At bronchoscopy all patients had a patent bronchial anastomosis. At postoperative DVI, in three patients, vascularization of the residual left lung was delayed and less intense compared with the non-operated right lung. Postoperative V/Q scan, in one patient, showed reduced ventilation and perfusion of the residual lung. Preoperative and postoperative FEV1 of the four patients were 2688/1998 ml, 2154/1752 ml, 2618/2100 ml and 2277/2015 ml. Operative mortality was zero. One patient had a postoperative atelectasis of the left lower lobe. In our series, ventilation and vascularization of the reimplanted and revascularized left lower lobe were reduced. But, in our opinion, the preserved residual lung parenchyma was still a relevant advantage.

Pulmonary function after sleeve lobectomy

Preoperative and postoperative pulmonary function of 109 sleeve lobectomy patients (90 right upper lobe, 10 left upper lobe, and 9 left lower lobe) were evaluated over a period of 30 years. Ninety-eight men and 11 women, with a mean age of 60 years, were reviewed. The diagnosis was lung cancer in 97 patients and carcinoid tumors in 12 patients. Indications for operation were anatomic suitability in 103 patients, and impaired pulmonary function (forced expiratory volume in 1 second (FEV1) less than 1,200 mL) in 6 patients. The predicted postoperative FEV1 was calculated and compared with the measured postoperative FEV1. Preoperative spirometry and split pulmonary radionuclide ventilation/perfusion scans were used to calculate the predicted postoperative FEV1. Postoperative spirometry had been performed 125 days after operation (range, 25 to 342 days). Our results showed a gradual improvement in postoperative pulmonary function. A complete and stable condition was reached 4 months after operation. Correlation between the predicted (mean, 2,097 mL) and measured FEV1 (mean, 2,067 mL) was good (linear regression and correlation test; r = 0.72). These values did not differ significantly (Wilcoxon signed rank test; p = 0.81). Our findings indicated a complete recovery of the reimplanted lung lobes after sleeve lobectomy.

Hemorrhage due to inflammatory erosion of the pulmonary artery stump in postpneumonectomy bronchopleural fistula

Bleeding from the pulmonary artery in patients with a bronchopleural fistula after pneumonectomy is a rare but devastating complication. The incidence is unknown, but our data suggest an incidence of 4% in all postpneumonectomy bronchopleural fistulas. Two case histories are presented in which the anterior transpericardial approach was used to stop the pulmonary bleeding by direct suturing. Nevertheless, 1 patient died 5 days later because of irreversible brain damage; the other patient recovered well after a protracted convalescence.

Mesenteric venous thrombosis caused by deficiency of physiologic anti-coagulants: report of a case

Mesenteric venous thrombosis is a clinical entity, which is rarely recognized on admission. The patients are admitted with vague abdominal complaints and, eventually, abdominal sepsis might occur requiring laparotomy. Nowadays, underlying hypercoagulable states such as antithrombin-III, protein-C and protein-S deficiencies are recognized more frequently as a distinct cause of mesenteric venous thrombosis. In this paper, a case of mesenteric venous thrombosis due to protein-C deficiency is presented. The patients generally have a history of thromboembolism of the deep veins of the legs at young age. The combination of vague abdominal complaints and a history of thrombosis of the deep veins of the legs should arouse the suspicion of mesenteric venous thrombosis. In these cases, contrast-enhanced computerized tomography is a non-invasive diagnostic means which may provide the diagnosis. If infarction of the gut is present, resection is mandatory and a second-look operation should be performed. After surgery, heparinization is essential. This must be followed by administration of oral anticoagulants for an indefinite period in case of an underlying antithrombin III, protein-C or protein-S deficiency.