BACKGROUND: Maze operation is aimed for the restoration of sinus rhythm. But restoration of atrial mechanical function has not been demonstrated in all patients converted to sinus rhythm. METHOD: From Apr. 1994 to Feb. 1996, maze operations were performed in 32 pts (M:F=13:19, mean age 47.1+/-9.0 years) combined with valvular surgery(n=26), CABG(n=3), and others(n=3). Presence of atrial mechanical function was serially examined before discharge, in 3mo, 6mo and 1 yr using Doppler echocardiography. RESULTS: In 22 patients(pts), sinus rhythm was maintained without antiarrhythmic agents. In 4 patients antiarrhythmic agent was required to maintain sinus rhythm while in another 4 patients showed paroxysmal Af despite of the treatment with antiarrhythmic agents. In 30 pts with sinus rhythm or paroxysmal Af, right atrial function was restored in all pts while left atrial function was restored in only 19/30(63%). Peak A velocity and A/E ratio were 0.38+/-0.12m/s, 0.74, respectively on tricuspid inflow(TI), and 0.46+/-0.14m/s, 0.40, respectively on mitral inflow(MI ). MI peak A velocity and A/E ratio were significantly lower than the 16 control postoperative pts (0.75<0.29, 0.80 : p+/-0.01). In pts with atrial mechanical function, the duration of Af was significantly shorter than patients without atrial function (1.9+/-2.9 yr vs 7.1+/-3.0 yr : p<0.01), but no significant differences in the LA size and volume. CONCLUSION: Maze operation is effective in restoring sinus rhythm. But restoration of sinus rhythm was not always associated with restoration of atrial mechanical function, and the restored atrial function was incomplete. The duration of Af could be a markker for predicting the restoration of atrial function.
Atrial Fibrillation ; Atrial Function ; Atrial Function, Left ; Atrial Function, Right ; Echocardiography, Doppler ; Humans

BACKGROUND: Maze operation is aimed for the restoration of sinus rhythm. But restoration of atrial mechanical function has not been demonstrated in all patients converted to sinus rhythm. METHOD: From Apr. 1994 to Feb. 1996, maze operations were performed in 32 pts (M:F=13:19, mean age 47.1+/-9.0 years) combined with valvular surgery(n=26), CABG(n=3), and others(n=3). Presence of atrial mechanical function was serially examined before discharge, in 3mo, 6mo and 1 yr using Doppler echocardiography. RESULTS: In 22 patients(pts), sinus rhythm was maintained without antiarrhythmic agents. In 4 patients antiarrhythmic agent was required to maintain sinus rhythm while in another 4 patients showed paroxysmal Af despite of the treatment with antiarrhythmic agents. In 30 pts with sinus rhythm or paroxysmal Af, right atrial function was restored in all pts while left atrial function was restored in only 19/30(63%). Peak A velocity and A/E ratio were 0.38+/-0.12m/s, 0.74, respectively on tricuspid inflow(TI), and 0.46+/-0.14m/s, 0.40, respectively on mitral inflow(MI ). MI peak A velocity and A/E ratio were significantly lower than the 16 control postoperative pts (0.75<0.29, 0.80 : p+/-0.01). In pts with atrial mechanical function, the duration of Af was significantly shorter than patients without atrial function (1.9+/-2.9 yr vs 7.1+/-3.0 yr : p<0.01), but no significant differences in the LA size and volume. CONCLUSION: Maze operation is effective in restoring sinus rhythm. But restoration of sinus rhythm was not always associated with restoration of atrial mechanical function, and the restored atrial function was incomplete. The duration of Af could be a markker for predicting the restoration of atrial function.
Atrial Fibrillation ; Atrial Function ; Atrial Function, Left ; Atrial Function, Right ; Echocardiography, Doppler ; Humans

CO2 and W produced in tissus come into venous blood. Can PCO2 and pH sampled from the right atrial blood via a central venous catether approriately replace the arterial PCO2 and pH in open hear surgery? Objectives: To evaluate the correlation and the agreement of PCO2 and of pH between the arterial and venous right atrial blood. Methods: Cross-over study with matched comparision, calculation of paired t test, coefficient of correlation r (Pearson), agreement (Bland-Altman). Results: Arterial-venous right atrial PC02: gradient-5.68 (+/-2.44), r = 0.92 and narrow agreement. Arterial-venous right atrial pH: gradient 0.04 (+/-0.02), r = 0.94 and narrow agreement. Conclusion: PCO2 and pH of the right atrial blood can safely replace the arterial PCO2 and pH in cardiac anesthesia and intensive care.
Thoracic Surgery ; Catheterization ; Hydrogen-Ion Concentration ; Atrial Function, Right

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a kind of inherited cardio-myopathy, which is characterized by fibro-fatty replacement of right ventricular myocardium, leading to ventricular arrhythmia. However, rapid atrial arrhythmias are also common, including atrial fibrillation, atrial flutter and atrial tachycardia. Long term rapid atrial arrhythmia can lead to further deterioration of cardiac function. This case is a 51-year-old male. He was admitted to Department of Cardiology, Peking University Third Hospital with palpitation and fatigue after exercise. Electrocardiogram showed incessant atrial tachycardia. Echocardiography revealed dilation of all his four chambers, especially the right ventricle, with the left ventricular ejection fraction of 40% and the right ventricular hypokinesis. Cardiac magnetic resonance imaging found that the right ventricle was significantly enlarged, and the right ventricular aneurysm had formed; the right ventricular ejection fraction was as low as 8%, and the left ventricular ejection fraction was 35%. The patients met the diagnostic criteria of ARVC, and both left and right ventricles were involved. His physical activities were restricted, and metoprolol, digoxin, spironolactone and ramipril were given. Rivaroxaban was also given because atrial tachycardia could cause left atrial thrombosis and embolism. His atrial tachycardia converted spontaneously to normal sinus rhythm after these treatments. Since the patient had severe right ventricular dysfunction, frequent premature ventricular beats and non-sustained ventricular tachycardia on Holter monitoring, indicating a high risk of sudden death, implantable cardioverter defibrillator (ICD) was implanted. After discharge from hospital, physical activity restriction and the above medicines were continued. As rapid atrial arrhythmia could lead to inappropriate ICD shocks, amiodarone was added to prevent the recurrence of atrial tachycardia, and also control ventricular arrhythmia. After 6 months, echocardiography was repeated and showed that the left ventricle diameter was reduced significantly, and the left ventricular ejection fraction increased to 60%, while the size of right ventricle and right atrium decreased slightly. According to the clinical manifestations and outcomes, he was diagnosed with ARVC associated with arrhythmia induced cardiomyopathy. According to the results of his cardiac magnetic resonance imaging, the patient had left ventricular involvement caused by ARVC, and the persistent atrial tachycardia led to left ventricular systolic dysfunction.
Arrhythmogenic Right Ventricular Dysplasia/complications* ; Atrial Fibrillation ; Humans ; Male ; Middle Aged ; Stroke Volume ; Ventricular Function, Left ; Ventricular Function, Right

BACKGROUND: The aim of study is to identify the dependence of right ventricular (RV) free wall longitudinal deformation on ventricular loading through segmental approach in relatively large number of patients with atrial septal defect (ASD). METHODS: Patients with ASD (n = 114) and age matched healthy children (n = 60) were echocardiographically examined the day before percutaneous device closure and within 24 hours afterwards. RV free wall deformation parameters, strain (small je, Ukrainian) and strain rate (SR), were analyzed in the apical (small je, Ukrainian(A), SR(A)) and basal (small je, Ukrainian(B), SR(B)) segments. Measured deformation parameters were adjusted for RV size (small je, Ukrainian(AL), SR(AL), small je, Ukrainian(BL), SR(BL)) by multiplying by body surface area indexed RV longitudinal dimension. Regression analyses determined the relationships of these deformation parameters with RV loading parameters that were measured by catheterization. RESULTS: small je, Ukrainian(BL) and SR(BL) were not different between pre-closure patients and controls (p = 0.245, p = 0.866), and were decreased post-closure (p = 0.001, p = 0.018). Post-closure small je, Ukrainian(BL) was lower than in controls (p = 0.001). Pre-closure small je, Ukrainian(AL) and SR(AL) were higher than in controls (p = 0.001, p < 0.001), but decreased after closure (all p < 0.001). The pulmonary to systemic flow ratio was related to procedural differences of small je, Ukrainian(BL) (p = 0.017) and of SR(BL) (p = 0.019). RV end diastolic pressure was negatively related to post-closure small je, Ukrainian(BL) (p = 0.020) and post-closure SR(BL) (p = 0.012), and the procedural SR(BL) difference (p = 0.027). CONCLUSION: The longitudinal deformation of the RV basal segment is dependent and its remodeling is also dependent on volume loading in children with ASD.
Blood Pressure ; Body Surface Area ; Catheterization ; Catheters ; Child* ; Heart Septal Defects, Atrial* ; Humans ; Ventricular Function, Right

OBJECTIVETo evaluate atrial remodeling induced by short term pacing in a canine model.

METHODSTransvenous lead was inserted into the right atrial appendage of anesthetized mongrel dogs and paced for 5 hours at 450 bpm (n=12). Effective refractory period (ERP) and P-wave duration were measured before and post pacing and left ventricular pressure was monitored during the procedure. Echocardiography was performed to observe the presence or absence of spontaneous echo contrast and to assess the effect of rapid atrial pacing on atrial function. All measurements were obtained in sinus rhythm. Histology of the myocardium in left atrial trabeculae and appendages was examined by electron microscopy.

RESULTSCompared to pre-pacing status, ERP was significantly reduced [(87.27 +/- 16.35) ms vs. (113.27 +/- 11.99) ms, P<0.01] at a cycle length of 300 ms, P-wave duration significantly increased [(56.09 +/- 8.62) ms vs. (52.09 +/- 7.63) ms, P<0.01], the peak velocity of atrial contraction significantly decreased [(48.92 +/- 10.80) cm/s vs. (59.25 +/- 9.37) cm/s, P<0.05] while heart rates and left ventricular pressure were not affected post five hours rapid atrial pacing. Pacing also induced significantly cellular ultrastructures changes including myofibrils loss, glycogen accumulation, mitochondria loss and swelling.

CONCLUSIONShort term pacing resulted in atrial electrical, contractile and structural remodeling.

Animals ; Atrial Fibrillation ; physiopathology ; therapy ; Atrial Function, Right ; Cardiac Pacing, Artificial ; methods ; Disease Models, Animal ; Dogs ; Female ; Male ; Myocardial Contraction

BACKGROUND AND OBJECTIVES: Heart failure rarely occurs in patients with thyrotoxicosis (6%), with half of the cases having left ventricular dysfunction (LVD). Although a few studies reported isolated right heart failure in thyrotoxicosis, there has been no evaluation of relationship between LVD and right ventricular dysfunction (RVD). SUBJECTS AND METHODS: We enrolled 12 patients (mean age: 51+/-11 years, 9 females) diagnosed as having thyrotoxicosis with heart failure and LVD {left ventricular ejection fraction (LVEF) <40%}, and divided them into two groups {Group I with RVD defined as tricuspid annular plane excursion (TAPSE) less than 15 mm and Group II without RVD}. Clinical features, laboratory variables, and echocardiographic parameters were compared between two groups. RESULTS: RVD was found in 6 (50%) patients. On admission, there were no significant differences between the two groups in clinical features, laboratory variables, or echocardiographic parameters including atrial fibrillation {6 vs. 5, not significant (NS)}, heart rate (149+/-38 vs. 148+/-32/min, NS), LVEF (36.7+/-9.5 vs. 35.1+/-6.3%, NS), or the tricuspid regurgitation peak pressure gradient (TRPPG, 30.9+/-2.0 vs. 36.3+/-9.3 mmHg, NS). After antithyroid treatment, all achieved an euthyroid state and both ventricular functions were recovered. All data, including the recovery time of LVEF and the change of heart rate between two groups, displayed no significant differences. CONCLUSION: In half of patients, RVD was combined with thyrotoxicosis-associated LVD. There were no differences in clinical factors or hemodynamic parameters between patients with and without RVD. This suggests that RVD is not secondary to thyrotoxicosis-associated LVD.
Atrial Fibrillation ; Heart Failure ; Heart Rate ; Hemodynamics ; Humans ; Stroke Volume ; Thyrotoxicosis ; Tricuspid Valve Insufficiency ; Ventricular Dysfunction, Left ; Ventricular Dysfunction, Right ; Ventricular Function

OBJECTIVETo investigate optimal time for early escharectomy after severe scald in minipigs.

METHODSMinipigs inflicted with 35% TBSA full thickness burn were employed in the study, and they were randomly divided into A (n = 7, with escharectomy at 6PSH), and B (n = 7, with escharectomy at 24 PSH) groups. The hemodynamics indices, hemorrheology, and the serum levels of cytokines in the two groups were determined before burns and at 6, 8, 16, 24 and 72PSH.

RESULTSThe hemodynamics indices in A group obviously improved compared with those in B group. The cardiac output (CO, 2.28 +/- 0.03 L/min) and right arterial pressure (RAP, 4.54 +/- 0.04 mmHg) in A group recovered to the pre-injury levels at 48 PSH. There was no difference of the hemorrheology indices between the two groups (P > 0.05). The serum contents of cytokines in A group declined to the pre-injury level on 1 PBW, while those in B group were significantly higher than those before injury and those in A group (P < 0.05 or P > 0.01).

CONCLUSIONEscharectomy during 6 PBH might be safe and feasible, thus preventing long-term complications effectively.

Acute-Phase Reaction ; Animals ; Atrial Function, Right ; Burns ; physiopathology ; surgery ; Cardiac Output ; Cytokines ; blood ; Disease Models, Animal ; Hemorheology ; Swine ; Swine, Miniature

The diameter and collapsibility of the inferior vena cava (IVC) should be interpreted in consideration with other clinical and echocardiographic parameters before drawing definitive diagnostic conclusions. We report a case of a 46-year-old female with isolated IVC dilation and diminished inspiratory collapse without other abnormalities, and provide a brief review of the literature.
Atrial Function, Right ; Atrial Pressure ; Cardiac Catheterization ; Dilatation, Pathologic ; Echocardiography, Doppler, Color ; Female ; Humans ; Middle Aged ; Phlebography/methods ; Respiratory Mechanics ; Tomography, X-Ray Computed ; Vena Cava, Inferior/*pathology/physiopathology/radiography/ultrasonography

PURPOSE: The association between pulmonary vein (PV) dilatation and stroke in non-valvular atrial fibrillation (AF) patients remains unknown. MATERIALS AND METHODS: We examined the left atrium (LA) and PV in control (n=138) and non-valvular AF patients without (AF group, n=138) and with non-hemorrhagic stroke (AF with stroke group, n=138) using computed tomography. RESULTS: The LA, LA appendage (LAA), and all PVs were larger in the AF than control patients. The orifice areas of the LAA (5.6+/-2.2 cm2 vs. 4.7+/-1.7 cm2, p<0.001), left superior PV (3.8+/-1.5 cm2 vs. 3.4+/-1.2 cm2, p=0.019), and inferior PV (2.3+/-1.0 cm2 vs. 1.8+/-0.7 cm2, p<0.001) were larger in the AF with stroke than in the AF only group. However, right PVs were not different between the two groups. In a multivariate analysis, the orifice areas of the left superior PV [odds ratio (OR) 1.25, 95% confidence interval (CI) 1.03-1.51, p=0.02], left inferior PV (OR 1.97, 95% CI 1.41-2.75, p<0.001), and LAA (OR 1.30, 95% CI 1.13-1.50, p<0.001) were independent predictors of stroke. CONCLUSION: Compared to the right PVs, the left PVs and LAA exhibited more significant enlargement in patients with AF and stroke than in patients with AF only. This finding suggests that the remodeling of left-sided LA structures might be related to stroke.
Aged ; Atrial Appendage/physiopathology/*radiography ; Atrial Fibrillation/*complications/diagnosis/physiopathology ; Atrial Function, Right/*physiology ; Female ; Heart Atria ; Humans ; Male ; Middle Aged ; Multidetector Computed Tomography/*methods ; Multivariate Analysis ; Odds Ratio ; Predictive Value of Tests ; Prognosis ; Pulmonary Veins/physiopathology/*radiography ; Stroke/diagnosis/*etiology ; Tomography, X-Ray Computed/methods