Diagnosis of left atrial thrombus with the aid of transesophageal echocardiography during aortic valve replacement: a case report

Transthoracic echocardiography and cardiac angiography are the most common tools used in this hospital for evaluation of cardiac disease. Yet the specificity of either method in detection of left atrial pathologies is unsatisfactory. In a 76-year-old male, severe aortic regurgitation with congestive heart failure was impressed from preoperative studies including transthoracic echocardiography and cardiac angiography. However, left atrial thrombus was further detected during routine intraoperative transesophageal echocardiography. Surgical evacuation of a left atrial thrombus was done before undertaking aortic valve replacement. The timely finding was crucial for prevention of further complication and for expeditious use of definite therapy.

Retrograde ascending aortic dissection diagnosed by intraoperative transesophageal echocardiography

Aortic dissection is a risky but challenging cardiovascular emergency and rapid surgical intervention for life-saving is sometimes inevitable. For detection of aortic dissection, computed tomography, magnetic resonance imaging, aortography all have their advantages but all have their limitations. Transesophageal echocardiography (TEE), which is portable and relatively noninvasive, is a highly sensitive and specific diagnostic tool for evaluation of aortic diseases. We presented a case in which preoperative imaging studies such as MRI and cardiac catheterization were all suggestive of DeBakey's type I aortic dissection. However, it was further proved to be a retrograde ascending aortic dissection during intraoperative TEE imaging study as a retrograde ascending blood flow was demonstrated within the dissected aortic lumen. So the initial operative scheme was changed and sternothoracoabdominal incision was selected for better exposure for one-stage repair of the entire thoracic aorta. Nevertheless, severe intrathoracic adhesion and case to bleed prevented any aggressive intervention to proceed. The operation was called off and the patient was transferred to ICU for further medical treatment.

Complete resolution of diastolic mitral regurgitation in chronic, but not acute aortic regurgitation after aortic valve replacement--a transesophageal echocardiography study

A 65-year-old male was admitted with progressive dyspnea on exertion. Severe aortic regurgitation (AR) had been disclosed by transthoracic echocardiography 10 mon previously. Aortic valve replacement was proposed and intraoperative transesophageal echocardiography on color Doppler imaging revealed severe aortic regurgitation, moderate global hypokinesis of the left ventricle and mild-to-moderate diastolic mitral regurgitation. The regurgitant jet was seen to pass through the posterior mitral leaflet in a direction toward the center of left atrium. Mitral valve perforation was suspected. But mitral valve was found to be intact after a thorough exploration. Surgery proceeded uneventfully and diastolic mitral regurgitation was resolved completely after the aortic valve was successfully replaced. Diastolic mitral regurgitation has been reported to be closely related to acute AR, but the picture differs somewhat from the present example. The possible cause for this disease presentation is to be further investigated.

Anesthesia for elective cardioversion: a comparison of thiopentone and propofol

BACKGROUND

Cardioversion is still a trend of therapy for cardiac dysrhythmias. With the application of new intravenous anesthetics, cardioversion can be performed safely and effectively with rapid onset of and quicker recovery from anesthesia. We compared the anesthetic effects of a new synthetic agent, propofol, with thiopentone which was mostly used in the past.

METHODS

Twenty four ASA class II to III adult patients scheduled for elective cardioversion in the coronary care unit were included in this study. All patients were given fentanyl (2 micrograms/kg, i.v.) three min before induction and were randomly assigned to receive either thiopentone 1.5 mg/kg (group 1) or propofol 1 mg/kg (group 2) for induction of anesthesia. Supplementary oxygenation was administered throughout.

RESULTS

Both drugs could provide satisfactory anesthesia for elective cardioversion without major complications. Recovery time was shorter with propofol (p < 0.05). Comparing with previous reports, a higher incidence of apnea and prolonged sedation were noted in this study. This might be due to the additive effect of thiopentone or propofol with fentanyl.

CONCLUSIONS

Both anesthetics were suitable for elective cardioversion with negligible side effects in hemodynamically stable patients.

The effect of single bolus dose of esmolol for controlling the tachycardia and hypertension during laryngoscopy and tracheal intubation

Tachycardia and hypertension usually accompany laryngoscopy and tracheal intubation. This response is undesirable, especially in patients with cardiovascular or intracranial diseases. Esmolol is a cardioselective, ultrashort-acting beta adrenergic blocking agent with a very short half-life. The efficacy of bolus dose of esmolol in blunting hemodynamic responses during laryngoscopy and tracheal intubation was evaluated. 45 patients (15 in each group) of ASA physical status I and II scheduled for elective non-cardiac surgery were included in this randomized, placebo-controlled study. At time zero, the study preparation (placebo, 100 or 200 mg of esmolol) was administered intravenously, followed by thiopentone 5 mg/kg and succinylcholine 1.5 mg/kg for induction. Tracheal intubation was performed 2 minutes after time zero. Anesthesia was maintained with 50% nitrous oxide and 1.0 MAC halothane in oxygen, and vecuronium 0.08 mg/kg. Heart rate (HR) and systolic blood pressure (SBP) were recorded every minute for 10 minutes. To compare with the placebo group, there was a significant decrease in either HR or SBP in 200 mg group in the 8 minutes course after intubation (p < 0.05). There was a significant decrease in HR in the 100 mg group at the 3rd, 4th, and 5th minutes when compared with the placebo group (p < 0.05). The differences in SBP between the 100 mg group and placebo group were significant at the 3rd and 4th minutes (p < 0.05). Both bolus dosages of esmolol could effectively attenuate the tachycardia and hypertension produced by laryngoscopy and tracheal intubation. Furthermore, esmolol 200 mg presented a better hemodynamic stability than esmolol 100 mg during induction of anesthesia.