Use of Intraoperative Transesophageal Echocardiography to Predict Atrial Fibrillation after Coronary Artery Bypass Grafting

Background: Postoperative atrial fibrillation in coronary artery bypass graft surgery occurs in 10-40% of patients. It is associated with a significant degree of morbidity and results in prolonged lengths of stay in both the intensive care unit and hospital.

Methods: The authors prospectively evaluated patients undergoing coronary artery bypass with detailed transesophageal echocardiography examinations conducted before and after cardiopulmonary bypass to study whether risk factors for atrial fibrillation could be identified. Demographic and surgical parameters were also included in the analysis. Selected variables were subjected to univariate and subsequent multivariate analyses to test for their independent or joint influence on atrial fibrillation.

Results: Seventy-nine patients had assessable transesophageal echocardiography examinations. Significant univariate predictors of atrial fibrillation included advanced age (P = 0.002), pre-cardiopulmonary bypass left atrial appendage area (P = 0.04), and post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio (P = 0.03). When these three factors were considered together in a multiple logistic regression analysis, left upper pulmonary vein systole/diastole velocity ratio was a significant predictor (P < 0.05), as was the joint effect of age plus pre-cardiopulmonary bypass left atrial appendage area (P = 0.005). The probability of developing atrial fibrillation for the combination of age = 75 yr, post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio = 0.5, and left atrial appendage area = 4.0 cm was 0.83 (95% confidence interval, 0.51-0.96).     

Transesophageal echocardiography values for left ventricular end-diastolic area and pulmonary vein and mitral inflow Doppler velocities in patients undergoing coronary artery bypass graft surgery

OBJECTIVE: To determine left ventricular end-diastolic area (EDA) and pulmonary vein and mitral inflow Doppler velocities in patients undergoing coronary artery bypass graft (CABG) surgery using transesophageal echocardiography (TEE). To examine the effects of age, sex, and left ventricular function on these values. DESIGN: Prospective observational study; all measurements performed before cardiopulmonary bypass. SETTING: Tertiary referral teaching hospital. PARTICIPANTS: Eighty-six elective CABG surgery patients. INTERVENTIONS: Intraoperative TEE was performed in all patients. MEASUREMENTS AND MAIN RESULTS: The left ventricular EDA was measured at the midpapillary level, excluding the papillary muscles. Mean EDA for patients with normal left ventricular function, defined by fractional area change (FAC) 0.50 or greater, was 10.66 cm2 and when indexed to body surface area was 5.6 cm2/m2. The EDA was greater in patients with impaired left ventricular function (FAC < 0.50). Mean EDA was 14.84 cm2, and EDA/body surface area was 7.8 cm2/m2. In patients with FAC 0.50 or greater, mean peak pulmonary vein Doppler velocities were 46.10 cm/sec (systole), 31.71 cm/sec (diastole), and 1.50 (ratio systole to diastole). Mean peak mitral inflow Doppler velocities were 57.25 cm/sec (early diastole), 57.21 cm/sec (late diastole), and 1.10 (ratio early to late), and deceleration time was 216 msec. Age, sex, and left ventricular function were not significant predictors of Doppler variables. CONCLUSIONS: Values are presented for a predominantly white population undergoing cardiac surgery. Left ventricular dysfunction is associated with increased left ventricular EDA measurements.     

Choice of venous cannulation for bypass during repair of traumatic rupture of the aorta

BACKGROUND: Choices for venous cannulation for left heart bypass, to assist repair of traumatic rupture of the thoracic aorta, are between the left atrial appendage and pulmonary veins. METHODS: A retrospective chart review was performed of patients who underwent operative repair of ruptured aorta. RESULTS: Over a 15-year period between March 1985 and February 2000, 133 patients were admitted to a level I trauma center with aortic rupture. Of the 50 procedures performed with left heart bypass, the left atrial appendage was cannulated in 19 and pulmonary veins in 31 (four superior, 27 inferior). Complications occurred in 7 of the 19 patients who underwent venous cannulation via the atrial appendage (two ventricular fibrillation, three atrial fibrillation, one pericardial effusion leading to tamponade, and one phrenic nerve injury). Complications occurred in 2 patients who underwent cannulation via pulmonary vein (one atrial fibrillation, one pericardial effusion requiring tapping) (p = 0.02). CONCLUSIONS: Cannulation via the pulmonary veins is associated with a decrease in complication rates compared with cannulation of the atrial appendage.     

Atrial fibrillation after coronary artery bypass graft surgery is unrelated to cardiac abnormalities detected by transesophageal echocardiography.

Atrial fibrillation is a common complication of coronary artery bypass graft (CABG) surgery that is associated with adverse patient outcomes. We evaluated whether preexisting abnormalities of cardiac structure or function detected with transesophageal echocardiography (TEE) are prevalent in patients later developing atrial fibrillation after CABG surgery. TEE imaging was performed after induction of general anesthesia, but before primary CABG surgery, in 62 consecutive patients without cardiac valvular disease or preexisting atrial fibrillation. Measurements included left atrial diameter, left ventricular wall thickness, left ventricular end-systolic and end-diastolic dimensions and fractional area change. Pulsed-wave Doppler measurements of pulmonary venous and trans-mitral blood flow velocity were obtained. Continuous monitoring with telemetry electrocardiography for the development of atrial fibrillation was performed. Eighteen patients (29%) developed postoperative atrial fibrillation. There were no significant differences in left atrial or left ventricular TEE variables or pulsed-wave Doppler pulmonary venous flow measurements between patients with and without postoperative atrial fibrillation. After adjusting for age and duration of aortic cross-clamping, there were no differences in the transmitral Doppler diastolic filling variables between these same groups. These data suggest that atrial fibrillation commonly occurs after CABG surgery in the absence of atrial enlargement or Doppler-derived cardiac functional abnormalities. The data imply that the use of TEE immediately before surgery would be an insensitive means for routine identification of patients susceptible to this arrhythmia. Implications: Transesophageal echocardiography performed immediately before coronary artery bypass graft (CABG) surgery is not useful for prediction of susceptibility to develop atrial fibrillation postoperatively. Postoperative atrial fibrillation commonly occurs after CABG surgery in the absence of preoperative atrial enlargement or Doppler derived functional abnormalities.     

A new procedure for chronic atrial fibrillation: bilateral appendage-preserving maze procedure.

BACKGROUND: Atrial transport and atrial natriuretic peptide secretion is severely reduced from normal after the maze III procedure. To improve these factors, we developed a bilateral appendage-preserving maze procedure (BAP-maze). METHODS: Forty-six patients with chronic atrial fibrillation who underwent the BAP-maze procedure were compared with 40 patients who underwent the maze III procedure. The ratio of the peak velocity of the A and E waves of transmitral flow (transthoracic pulsed Doppler echocardiography), the left atrial appendage ejection fraction (transesophageal echocardiography), and the atrial natriuretic peptide secretory reserve during treadmill exercise test were measured at 6 months postoperatively. RESULTS: Sinus rhythm was restored in 44 patients (95.7%) by the BAP-maze procedure and in 39 patients (97.5%) by the maze III procedure. The ratio of the peak velocity of the A and E waves was 0.52 +/- 0.22 in the BAP-maze group and 0.25 +/- 0.19 in the maze III group (p < 0.0001). The left atrial appendage ejection fraction was 44.7% +/- 11.5%, and the atrial natriuretic peptide secretory reserve was greater in the BAP maze group (p = 0.037). CONCLUSIONS: The BAP-maze procedure improved atrial transport and atrial natriuretic peptide secretion as well as simplifying the maze operation, without decreasing its effectiveness against atrial fibrillation.     

Uso da ecocardiografia transesofágica no período perioperatório orientando a tomada de decisão durante a instabilidade hemodinâmica desencadeada por fibrilação atrial

Background and objective

Atrial fibrillation is the most common cardiac arrhythmia, which may occur during the perioperative period and lead to hemodynamic instability due to loss of atrial systolic function. During atrial fibrillation management, electrical cardioversion is one of the therapeutic options in the presence of hemodynamic instability; however, it exposes the patient to thromboembolic event risks. Transesophageal echocardiography is a diagnostic tool for thrombi in the left atrium and left atrial appendage with high sensitivity and specificity, allowing early and safe cardioversion. The present case describes the use of transesophageal echocardiography to exclude the presence of thrombi in the left atrium and left atrial appendage in a patient undergoing non‐cardiac surgery with atrial fibrillation of unknown duration and hemodynamic instability.

Left atrial appendage outflow velocity index is superior to conventional criteria for prediction of maintenance of sinus rhythm after cardioversion. An echocardiographic study in patients with atrial fibrillation of a few months' duration

OBJECTIVE: To investigate whether left atrial appendage outflow velocity alone or in relation to left atrial diameter is a superior predictor of sinus rhythm maintenance after cardioversion compared with traditional clinical or echocardiography parameters. DESIGN: Sixty-two patients with their first episode of atrial fibrillation were examined using echocardiography before DC-cardioversion. At one month's follow-up, 42 patients had maintained sinus rhythm (group A), and 20 had relapsed into atrial fibrillation (group B). There were no differences in arrhythmia duration or antiarrhythmic therapy between the groups. RESULTS: Left atrial diameter measured by echocardiography was smaller in group A (42 mm, 95% CI 40.9-44.1 mm) compared with group B (46 mm, 95% CI 43.4-48.2, p < 0.05). Patients in group A had a higher left atrial appendage outflow velocity at 0.44 m/s (95% CI 0.39-0.49) compared with 0.34 m/s (95% CI 0.30-0.37) in group B (p < 0.01). The ratio of left atrial appendage flow to left atrial diameter was 0.011 (95% CI 0.009-0.012) in group A compared with 0.008 (95% CI 0.007-0.009) in group B, and 63% (95% CI 33-78) of the patients in group A had velocity ratio >0.009 compared with 20% (95% CI 2-38) in group B, (p < 0.01). Stepwise multiple logistic regression analysis showed that a velocity ratio >0.009 was the only predictor for maintenance of sinus rhythm one month after cardioversion with an odds ratio of 6.4 (95% CI 1.9-23.8), (p = 0.004). CONCLUSION: The ratio of left atrial appendage outflow velocity to left atrial diameter is superior to the traditionally used criteria for prediction of maintenance of sinus rhythm following DC-conversion of first-episode atrial fibrillation.     

Assessing the immediate and sustained effectiveness of circular epicardial surgical ligation of the left atrial appendage

Abstract Background/Aim: Obliterating the left atrial appendage from systemic circulation in patients with atrial fibrillation has been proposed to reduce thromboembolic events. The goal of this study was to assess the effectiveness of a circular method of epicardial surgical ligation in obliterating the left atrial appendage and maintaining sustained exclusion. Methods: Patients with permanent atrial fibrillation and an indication for elective cardiac surgery were enrolled. All patients underwent preoperative cardiac gated computerized tomography (CT) and transesophageal echocardiography (TEE). During the cardiac procedure circular ligation of the appendage was performed. Results: Twelve patients, mean (SD) age 65 (12) years completed the study. Intraoperative TEE demonstrated all patients (12/12) had complete postligation occlusion of the left atrial appendage. At three‐month follow‐up, cardiac gated CT demonstrated that 75% (9/12) of the patients had communication of contrast dye from the left atrial appendage to body of left atrium. Left atrial appendage orifice area and volume were reduced from mean (SD) (5.5 cm²[1.8] to 0.5 cm²[0.4] p = 0.002) and (14.0 cm³[8.3] to 2.7 cm³[1.3] p = .005) postligation, respectively. No clinically significant thromboembolic events were reported. Conclusions: Epicardial suture ligation of the left atrial appendage resulted in successful intra‐operative exclusion on TEE; however, a significant portion of patient's demonstrated communication of contrast on CT. This is suggestive of incomplete long‐term exclusion. The clinical significance of reduction in left atrial appendage orifice area and volume with a persistent communication requires further study.     

Anesthesia for a patient with cardiac sarcoidosis

Anesthesia for a 49-year-old man with cardiac sarcoidosis is reported. Preoperative cardiac examination showed left ventricular dysfunction (ejection fraction = 27%) and myocardial conduction defects. In addition, his previous history included atrial fibrillation and cerebral infarction. Transesophageal echocardiography showed thrombus in the left appendage. Anesthesia was induced with fentanyl and diazepam and maintained with fentanyl and isoflurane. Perioperative hemodynamic monitoring included direct arterial pressure, central venous and pulmonary artery pressure and continuous cardiac output. In addition, transesophageal echocardiography was useful for watching thrombus in the left appendage. His hemodynamic condition was stable and no neurological complication was noted after anesthesia.     

Video-assisted bilateral pulmonary vein isolation and left atrial appendage exclusion for atrial fibrillation

OBJECTIVE: Pulmonary vein isolation is curative in selected patients with atrial fibrillation. The objective of this study was to assess the feasibility and safety (midterm results) of video-assisted thoracoscopic epicardial pulmonary vein isolation. METHODS: Twenty-seven patients (22 male patients) with atrial fibrillation (18 paroxysmal, 4 persistent, and 5 permanent; average age, 57 years) underwent bilateral video-assisted thoracoscopic off-pump epicardial pulmonary vein isolation and exclusion of the left atrial appendage. All patients had had unsuccessful drug therapy or were intolerant to antiarrhythmic drug therapy or were intolerant to warfarin. The approach included two 10-mm ports and one 5-cm working port (non-rib spreading) bilaterally. Pulmonary vein isolation was achieved bilaterally by using a bipolar radiofrequency device. The left atrial appendage was excised with a surgical stapler. RESULTS: Bilateral pulmonary vein isolation and left atrial appendage excision was performed successfully in all patients. There were no conversions to sternotomy or thoracotomy. All patients were extubated in the operating room. Postoperative complications in 3 patients were minor and resolved within 48 hours. One morbidly obese patient had more serious complications related to comorbid conditions. Average postoperative follow-up is approximately 6 months (173.6 days). Twenty-three patients have been followed up for greater than 3 months, and 21 of these patients are free of atrial fibrillation (91.3%). The results of magnetic resonance angiography were normal (no pulmonary vein stenosis) in 12 of 12 patients evaluated 3 to 6 months postoperatively. CONCLUSIONS: Bilateral video-assisted thoracoscopic pulmonary vein isolation with excision of the left atrial appendage is feasible and safe and offers a promising, new, minimally invasive, beating-heart approach for curative surgical treatment of atrial fibrillation.     

Map-guided surgery for atrial fibrillation

BACKGROUND: Although current surgical procedures result in a high success rate for atrial fibrillation, they are not guided by electrophysiologic findings in individual patients and thus might include unnecessary incisions in some patients or be inappropriate for other patients. We sought to determine whether intraoperative mapping is beneficial for the surgical treatment of atrial fibrillation. METHODS: A 256-channel 3-dimensional dynamic mapping system with custom-made epicardial patch electrodes was used to examine the atrial activation during atrial fibrillation and to determine the optimal procedure in 37 patients with continuous and 9 patients with intermittent atrial fibrillation intraoperatively. RESULTS: Surgical intervention for atrial fibrillation was not indicated in 3 patients in whom the atrial electrograms had a low voltage over a broad area. Concurrent, multiple, and repetitive activations arising from the pulmonary veins or left atrial appendage were observed in all patients. A simple left atrial procedure consisting of pulmonary vein isolation and left atrial incisions without any right atrial incisions was performed in 8 patients in whom the right atrial activation was passive, and all (100%) were cured of atrial fibrillation. The radial procedure was performed in the remaining 35 patients, and 31 (89%) of the patients were cured of atrial fibrillation. In this subset of patients, 10 exhibited reentrant or focal activation in the posterior left atrium between the right and left pulmonary veins and required an additional linear ablation on the posterior left atrium. The total amount of postoperative bleeding after the simple left atrial procedure was significantly less than after the radial procedure (378 +/- 135 vs 711 +/- 364 mL, P = .03). The right and left atrial transport functions were well preserved after both the radial and simple left atrial procedures. CONCLUSION: Intraoperative mapping facilitates determining the optimal procedure for atrial fibrillation in each patient.     

Left Atrial Appendage Outflow Velocity Index is Superior to Conventional Criteria for Prediction of Maintenance of Sinus Rhythm after Cardioversion. An Echocardiographic Study in Patients with Atrial Fibrillation of a Few Months' Duration

Objective - To investigate whether left atrial appendage outflow velocity alone or in relation to left atrial diameter is a superior predictor of sinus rhythm maintenance after cardioversion compared with traditional clinical or echocardiography parameters. Design - Sixty-two patients with their first episode of atrial fibrillation were examined using echocardiography before DC-cardioversion. At one month's follow-up, 42 patients had maintained sinus rhythm (group A), and 20 had relapsed into atrial fibrillation (group B). There were no differences in arrhythmia duration or antiarrhythmic therapy between the groups. Results - Left atrial diameter measured by echocardiography was smaller in group A (42 mm, 95% CI 40.9-44.1 mm) compared with group B (46 mm, 95% CI 43.4-48.2, p &lt; 0.05). Patients in group A had a higher left atrial appendage outflow velocity at 0.44 m/s (95% CI 0.39-0.49) compared with 0.34 m/s (95% CI 0.30-0.37) in group B (p &lt; 0.01). The ratio of left atrial appendage flow to left atrial diameter was 0.011 (95% CI 0.009-0.012) in group A compared with 0.008 (95% CI 0.007-0.009) in group B, and 63% (95% CI 33-78) of the patients in group A had velocity ratio &gt;0.009 compared with 20% (95% CI 2-38) in group B, (p &lt; 0.01). Stepwise multiple logistic regression analysis showed that a velocity ratio &gt;0.009 was the only predictor for maintenance of sinus rhythm one month after cardioversion with an odds ratio of 6.4 (95% CI 1.9-23.8), (p = 0.004). Conclusion - The ratio of left atrial appendage outflow velocity to left atrial diameter is superior to the traditionally used criteria for prediction of maintenance of sinus rhythm following DC-conversion of first-episode atrial fibrillation.     

风湿性二尖瓣狭窄左心房血栓形成的危险因素分析

目的 探讨风湿性二尖瓣狭窄左心房血栓形成的危险因素.方法 2001年1月至2008年12月,2277例风湿性二尖瓣狭窄病人接受手术治疗,男737例,女1540例;年龄19～84岁,平均(50.9±10.2)岁.按左心房有无血栓分为血栓组(554例)和无血栓组(1723例).回顾性分析入选病例的一般资料、心电图、超声心动图及实验室检查资料.对单因素分析中有统计学意义的指标行多因素回归分析.结果 单因素分析发现年龄、二尖瓣瓣口面积、左心房内径、左室舒张末径、C反应蛋白、性别、二尖瓣狭窄程度、二尖瓣反流程度、三尖瓣反流程度、肺动脉高压程度、房颤和心功能分级共12个因素组间差异有统计学意义.多因素回归分析发现年龄、二尖瓣瓣口面积、左心房内径、二尖瓣反流程度、房颤是风湿性二尖瓣狭窄病人左心房血栓形成的主要影响因素.结论 风湿性二尖瓣狭窄病人年龄、二尖瓣瓣口面积、左心房内径、房颤是并发左心房血栓的主要危险因素.二尖瓣反流可以降低左心房血栓形成的风险,是左心房血栓形成的保护性因素.

Abstract：

Objective To analysis of risk factors for left atrial thrombosis in patients with rheumatic mitral stenosis.Methods From January 2001 to December 2008, 2277 patients with rheumatic mitral stenosis underwent operations in our hospital. There were 737 males and 1540 female, the age ranged from 19 to 84 years [average (50.9 ±10.2) years]. Left atrial thrombosis group (554 cases) and no thrombosis group (1723 cases) were divided, retrospectively collected data were analyzed with univariate and multivariate Logistic regression. Results 12 bvariables, including age, mitral valve orifice area, left atrial diameter, left ventricular diastole diameter, CRP, gender , degree of mitral stenosis, or regurgitation, degree of bicuspid regurgitation, degree of pulmonary hypertension, atrial fibrillation and heart function had statistic difference between two groups. With multivariate Logistic regression for these 12 factors, age, mitral valve orifice area, left atrial diameter, degree of mitral regurgitation and atrial fibrillation were found to be the affecting factors for left atrial thrombosis in patients with rheumatic mitral stenosis. Conclusion For patients with rheumatic mitral stenosis, age, mitral valve orifice area, left atrial diameter and atrial fibrillation are the risk factors for left atrial thrombosis. Mitral regurgitation is a protective factor for left atrial thrombosis.     

Effects of atrial fibrillation on coronary artery bypass graft flow.

OBJECTIVES: No detailed studies exist of coronary artery bypass graft flow during atrial fibrillation. We examined the effects on bypass graft flow of atrial fibrillation following coronary artery bypass grafting. METHODS: Immediately after surgical revisualization, atrial fibrillation was induced in 18 patients by high frequency atrial pacing. Hemodynamic variables were measured in sinus rhythm and atrial fibrillation. The graft flow in pedicled left internal thoracic artery grafts and in saphenous vein grafts was also measured using transit-time flowmetry. RESULTS: Left internal thoracic artery graft flow had a greater diastolic component than saphenous vein graft flow, as shown by the percent diastolic time-flow integral (86 +/- 10% in the left thoracic artery and 62 +/- 12% in the saphenous vein, P < 0.0001). The induced atrial fibrillation caused significant deterioration in hemodynamics: heart rate and central venous pressure increased, and mean arterial pressure and cardiac index decreased (all P < 0.0025). In left internal thoracic artery grafts (n = 18) and also in saphenous vein grafts (n = 20), graft flow decreased significantly with atrial fibrillation (44.3 +/- 26.2 to 26.2 +/- 20.7 ml/min in the left internal thoracic artery, P = 0.0003; 39.7 +/- 15.6 to 33.3 +/- 14.3 ml/min in the saphenous vein, P = 0.001). The reduction in graft flow due to atrial fibrillation was much larger in left internal thoracic artery grafts than in saphenous vein grafts (P = 0.0008). CONCLUSIONS: Direct measurement of coronary artery bypass graft flow shows that atrial fibrillation after surgery significantly reduces graft flow. The effect is much larger in left internal thoracic artery grafts with their strong diastolic component than in saphenous vein grafts.     

Tei指数评价冠心病合并房颤患者左心室功能

目的探讨Tei指数评价冠心病（CHD）合并心房颤动（AF）患者左心室功能的临床应用价值。方法 60例CHD合并AF患者分为两组：快速AF组30例（心率≥120次/分）,慢速AF组30例（心率〈120次/分）;另选取30名健康人作为对照组。应用多普勒超声心动图检测左心室Tei指数及各传统指标,包括二尖瓣舒张早期血流峰值速度（E峰）、舒张晚期血流峰值速度（A峰）、E峰减速时间（DT）、瓣环平均收缩期血流速度（Sm）、平均舒张早期血流速度（Em）、平均舒张晚期血流速度（Am）、E/Em及左心室射血分数（LVEF）;并进行统计学分析。结果与对照组相比,CHD合并AF各组Tei指数明显升高（P〈0.05）。快速AF组与慢速AF组比较,Tei指数差异有统计学意义（P〈0.05）。Tei指数与E峰、E/Em正相关,与DT、Em、Sm、LVEF呈负相关。结论 Tei指数可用以评价CHD合并AF患者的左心室功能。     

Improved Surgical Approach to Left Atrial Appendage Aneurysm

Left atrial appendage aneurysm is a rare anomaly, which usually presents with arrhythmia or cerebral embolism. Diagnostic evaluation traditionally required cardiac catheterization, and surgical resection required cardiopulmonary bypass. Utilizing intraoperative transesophageal echocardiography and surgical stapling devices, we have streamlined our operative technique, allowing resection of a left atrial appendage aneurysm without cardiopulmonary bypass. This report of two cases treated over the past decade demonstrates the evolution of our surgical technique.     

Encircling isolation of pulmonary vein orifice for elimination of persistent atrial fibrillation associated with mitral valve disease

The authors treated a 70-year-old woman with persistent atrial fibrillation associated with mitral valve stenosis. Restoration of sinus rhythm was achieved with encircling isolation of pulmonary vein orifices concomitant with mitral valve replacement. A vertical incision in the right side of left atrium was extended to the margin of the upper and lower left pulmonary vein orifices. Supplemental cryo-coagulation was applied to the remnant of the circular incision, avoiding the entire encircling incision. Consequently, all pulmonary veins were electrically isolated. Encircling pulmonary vein orifice isolation is less invasive than the MAZE procedure because of reductions in surgical time and cardiopulmonary bypass time, minimization of atrial incisions, and prevention of injury to the coronary artery. It is thus an effective option for selected patients with atrial fibrillation.     

Para-esophageal anastomosis of left atrium in orthotopic heart transplantation in dogs: possibility for electrophysiologic examination of the transplanted heart with transesophageal atrial stimulation

Para-esophageal anastomosis of left atrium was examined in orthotopic heart transplantation as a new surgical technique for transesophageal electrophysiologic study of the transplanted heart. Seven orthotopic heart transplantations were performed in mongrel dogs. Left atrial appendage of the donor heart was trimmed as a flap and the sinus venosus of right atrium was incised posteriorly. An upper midline incision was made in the posterior wall of left atrium of the recipient after native ventricles were resected. Left atrial appendage flap of the donor heart was anastomosed to the posterior incision of native left atrium, and the remains of left atrium were sutured continuously. Sinus venosus incision of the donor heart was anastomosed to the right atrium of recipient. Ascending aorta and pulmonary trunk were reconstructed in the standard fashion. Transesophageal atrial pacing was possible during and after weaning from cardiopulmonary bypass in all seven cases. The appendage flap was found to occupy one third of the posterior wall of left atrium at the time of sacrifice. It was suggested that para-esophageal anastomosis of left atrium would be an useful technique for transesophageal electrophysiologic study of the transplanted heart.     

Effects of preoperative treatment with diltiazem on diastolic ventricular function after coronary artery bypass graft surgery

OBJECTIVE: To examine whether preoperative treatment with diltiazem could ameliorate left ventricular (LV) diastolic dysfunction in patients after coronary artery bypass graft (CABG) surgery. DESIGN: Prospective, nonrandomized clinical study. SETTING: University hospital. PARTICIPANTS: Thirty-four patients with preserved LV function undergoing elective CABG surgery. INTERVENTIONS: According to medical history, patients were divided into 2 groups: patients not receiving diltiazem (n = 17) and patients treated with once-daily oral diltiazem for at least 2 weeks (n = 17). All patients received preoperative beta-blockers. MEASUREMENTS AND MAIN RESULTS: After induction of anesthesia, after sternal closure, and 4 hours after cardiopulmonary bypass (CPB), mitral and pulmonary venous flow velocities were measured with pulsed Doppler. LV short-axis end-diastolic area by Doppler transesophageal echocardiography (TEE) and hemodynamic variables were obtained simultaneously at comparable pulmonary capillary wedge pressures. Postoperatively, increased peak E and A velocities were observed in patients with diltiazem and controls and returned to baseline 4 hours post-CPB in controls. Changes in these velocities did not result in a decreased E/A ratio. Peak A velocity, E/A ratio, and E wave deceleration time were significantly dependent on heart rate, not peak E velocity. End-diastolic area at comparable pulmonary capillary wedge pressure remained unchanged. In relation to diltiazem, only peak A velocity and time velocity integral of the A wave (TVI-A) at 4 hours post-CPB differed from controls. CONCLUSION: Diastolic function is preserved after CABG surgery and is not altered by diltiazem in patients with preserved LV systolic function. The persistence of increased peak A velocity and TVI-A into the postoperative period suggests improved atrial systolic function with diltiazem.     

Left Atrial ball thrombi without mitral valve disease treated by surgical removal

We describe two patients with free-floating left atrial ball thrombi with no evidence of cardiac disease except atrial fibrillation. One patient had experienced an embolic stroke, and the second patient had a history of stroke and peripheral thromboembolism. In each patient, the thrombi, which were not visible on transthoracic echocardiography, were detected by transesophageal echocardiography. Each patient underwent successful surgical removal using cardiopulmonary bypass.