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Total of 41 patients with tetralogy of Fallot (TOF) who underwent intracardiac repair from 1993 to 1998 were divided into 2 groups: preservation (n = 14) or enlargement (n = 27) of the pulmonary valve annulus. The procedure was decided on the Z value of the annular size: above or under -2 SD of the standard value. Although postoperative right ventricular (RV) diastolic volume (RVEDV) and cardiothoracic ratio (CTR) were larger than the preservation group and pulmonary regurgitation (PR) existed in the enlargement group, RV pressure was decreased and central venous pressure (CVP) was low and RV contraction was preserved. The exercise capacity was also good and no significant arrhythmia was recognized. Our mid-term results showed that appropriate enlargement of the pulmonary valve annulus preserved good RV function in patients with TOF.

We performed a unilateral pulmonary arterial occlusion (UPAO) test for the preoperative evaluation of right ventricular functions as a loading test in patients undergoing a lung resection without cardiac complications preoperatively. We investigated the relationship between changes in right ventricular hemodynamic functions and postoperative cardiac complications, namely right heart failure or arrhythmia. To evaluate the right ventricular hemodynamic function test, we measured the mean pulmonary arterial pressure, cardiac index, right ventricular ejection fraction end-diastolic volume, and stroke volume before and during the UPAO test using the thermodilution method, and calculated the total pulmonary vascular resistance and right ventricular stroke work indexes. The incidence of postoperative cardiac complications was not related to the changes in the total pulmonary vascular resistance index. However, the postoperative cardiac complications were common in patients whose right ventricular end-diastolic volume index was increased by more than 20% during the UPAO test. These results suggest that the changes in the right ventricular end-diastolic volume index during the UPAO test can predict postoperative cardiac complications in patients undergoing a pulmonary resection.

We evaluated postoperative right ventricular function in the sixty-four consecutive patients with tetralogy of Fallot underwent total correction. The patients were divided to three groups according to the method of right ventricular outflow tract reconstruction: transannular patching (TA group; n = 31); right ventricular outflow patching with preservation of pulmonary valve ring (RV group; n = 12) and transatrial-transpulmonary approach without right ventriculotomy (no-RV group; n = 21). The early results of postoperative cardiac catheterization and echocardiography were compared among the three groups. Degree of pulmonary regurgitation was significantly low in the RV group and no-RV group compared with TA group (p < 0.005). Right ventricular ejection fraction was the highest in the no-RV group (p < 0.002). The repair without right ventriculotomy for tetralogy of Fallot can provide the best results with respect to postoperative right ventricular function.

Clinical applications of nuclear medicine in pulmonary hypertension (PH) include: 1) Differentiation of primary from chronic thromboembolic form of PH by mismatched ventilation/perfusion defects, 2) Quantification of right ventricular ejection fraction to estimate cardiac functional derangement, 3) Estimation of right ventricular hypertrophy or pressure overload by increased accumulation of radioactive myocardial perfusion agents, and 4) Estimation of myocardial sympathetic nervous function or fatty acid metabolism. Gravity dependent shift of pulmonary perfusion detected by perfusion scintigraphy has also been utilized for estimating severity of PH. Positron emission tomography (PET) has visualized distribution of pulmonary adrenergic receptors and angiotensin converting enzyme. PET, in addition to F-18 FDG lung tumor PET, should be watched for because it may visualize and quantify other bioactive substances and receptors in the lung.

Although computed tomography (CT) and magnetic resonance imaging (MRI) can not measure the pulmonary arterial pressure, those can depict the morphological changes due to pulmonary hypertension, which are dilatation of main and central pulmonary artery, right ventricular hypertrophy and dilatation of right ventricle, right atrium, vena cava and coronary sinus. Right ventricular volume, mass and ejection fraction are calculated quantitatively by MRI using Simpson method. Thromboembolism can be detected by enhanced CT. Information about pulmonary blood flow and tricuspid regurgitation are given by MRI. Three dimensional MR angiography depicts the pulmonary artery as a whole. CT and MRI can detect pulmonary and congenital heart disease, the cause of pulmonary hypertension. CT and MRI are useful complementary method for evaluating pulmonary hypertension.

Objectives: Left ventricular Doppler index (LVDI) is believed to be a useful echocardiographic index of systolic and diastolic ventricular function. However, the usefulness of right ventricular Doppler index (RVDI) remains uncertain, especially in dilated cardiomyopathy. The predictive value of RVDI for estimating long-term cardiac events, including cardiac death, was investigated., Methods: Fifty-nine consecutive patients with dilated cardiomyopathy (41 males and 18 females, mean age 52 +/- 15 years) were enrolled in this follow-up study. RVDI and LVDI were calculated as follows: DI = (isovolumic contraction time + isovolumic relaxation time)/ejection time., Results: During a follow-up period of 3.7 +/- 3.0 years, 27 (46%) of the patients exhibited cardiac events, including cardiac death (n = 9), heart failure (n = 16) and tachyarrhythmias (n = 2) requiring in-hospital treatment. Patients with these cardiac events had higher LVDI and RVDI at the initial follow-up examination, and RVDI had a significant linear correlation with LVDI (LVDI = 0.550 + 0.452 x RVDI, r = 0.530, p = 0.0001). The 6-year survival rate was significantly lower in patients with both LVDI > or = 0.78 and RVDI > or = 0.49 than in other patients (50% vs 75%, respectively, p = 0.009). Cox proportional hazards model analysis showed that RVDI > or = 0.49 was the independent predictor of cardiac events (p = 0.0153) and cardiac death (p = 0.0003)., Conclusions: RVDI is clinically useful for estimating the outcome of patients with dilated cardiomyopathy.

We evaluated right and left ventricular function by intraoperative transesophageal echocardiography for the patients with left ventricular dysfunction (left ventricular ejection fraction (LVEF) < or = 40) who underwent isolated coronary artery bypass grafting (CABG). We divided these patients into two groups; group 1 who had difficulty of weaning from cardiopulmonary bypass due to hypotension (n = 8) and group 2 who did not have any difficulty of it (n = 17). Basement characteristics (age, gender, history of myocardial infarction, congestive heart failure, LVEF, severity of the right coronary artery disease) of both groups were not different significantly. Intraoperative characteristics (the number of distal anastomoses, duration of aortic cross-clamp and cardiopulmonary bypass, and bypass to the right coronary artery) were also not different between two groups. However, mean duration of ICU stay and in-hospital mortality were significantly longer and higher in group 1 than group 2. On the other hand, right ventricular systolic function was severely impaired, particularly postoperatively, in group 1 compared with group 2. Right and left ventricular systolic function of group 2 was fairly improved postoperatively. These results may indicate that right ventricular dysfunction is a potent predictor of postoperative morbidity and mortality for the patients with left ventricular dysfunction who undergo isolated CABG.

Background: The Ross procedure requires the interposition of prosthetic or homograft extracardiac conduits to establish ventricle-pulmonary artery connection (RV-PA). These materials usually require multiple reoperations because of conduit failure. To avoid the re-replacement of currently available conduits, usage of autologous tissue may be preferable to reconstruct RV-PA connection during the Ross procedure, especially in the pediatric age group., Method: Ten patients (mean age 8.7 years, range 2-23) with congenital aortic valve disease underwent the Ross procedure between June, 1996 and July, 1998. To establish RV-PA continuity, autologous aortic wall including aortic valve with a gusset of pericardial tissue was used in six patients, rolled pericardial conduit with fresh pericardial bicuspid valve in three and one direct anastomosis of pulmonary posterior wall onto the right ventricle with a fresh pericardial monocusp valved patch. All patient's postoperative courses were uneventful. All patients were followed up (mean follow-up period: 21.6 +/- 6.6 months) and postoperative right ventricular characteristics, cardio-thoracic ratio (CTR) on chest X-ray and pulmonary valve function were evaluated., Results: Postoperative right ventricular end-diastolic volume, right ventricular ejection fraction and right ventricular end-diastolic pressure did not change significantly (RVEDV: 128 to 113% of normal, RVEF: 56.4 to 51.5%, RVEDP: 5.9 to 10.1 mmHg). Pulmonary regurgitation during follow-up was mild in six patients and moderate in four. However, CTR decreased significantly over time (preop.: 56.5% postop.: 58.5%, late period: 53.4%)., Conclusion: Our results support the concept of the reconstruction of pulmonary outflow tract without foreign materials during the Ross procedure. Longer follow-up are necessary to define the possible limitation of this technique.

Systemic venous return to the heart is disturbed as a result of right heart failure. ICG clearance is known to be influenced by hepatic venous return to the right atrium. Under a hypothesis that right heart function could be evaluated by ICG clearance test, patients with mitral valve disease (Group M, n = 29), aortic valve disease (Group A, n = 16), ischemic heart disease (Group CABG, n = 19) were studied. Preoperative K-ICG (normal range > 0.17) in the Group M was significantly lower than those in the Group A and Group CABG (0.097 +/- 0.037 vs 0.166 +/- 0.032 and 0.171 +/- 0.027, p < 0.05). In the Group M, patients who underwent tricuspid annuloplasty (TAP) had significantly lower K-ICG than the others (0.077 +/- 0.026 vs 0.113 +/- 0.038, p < 0.05). Postoperatively, K-ICG of TAP patients significantly increased (0.092 +/- 0.031, p < 0.05) when compared to their preoperative value. ICG clearance test was useful to quantify the right heart function, especially in the postoperative evaluation.

The effects of right ventricular outflow pacing were studied in 13 patients (mean [+/-SD] 69.8 +/- 8.2 years old). All patients received DDD pacemakers except two patients with implanted VVI pacemakers who had chronic atrial fibrillation. Cardiac output and pulmonary capillary wedge pressure were measured by Swan-Ganz catheter. Pacing rate was fixed at 70-80/min and atrioventricular delay was fixed at 165 msec. When the pacing site was changed from the right ventricular apex to the right ventricular outflow during right ventricular pacing in 11 patients, cardiac output increased from 3.3 +/- 0.6 to 3.4 +/- 0.5 l/min (p < 0.001), and wedge pressure decreased from 9.3 +/- 1.9 to 8.8 +/- 2.0 mmHg (p < 0.05). When the pacing site was changed from the right ventricular apex to the right ventricular outflow during atrioventricular pacing in eight patients, cardiac output increased from 3.9 +/- 0.4 to 4.0 +/- 0.4 l/min (p < 0.05), and wedge pressure decreased from 7.1 +/- 2.3 to 6.6 +/- 2.1 mmHg (p < 0.05). When the pacing site was changed from the right ventricular apex to the right ventricular outflow in seven patients with ejection fraction (EF) greater than 55%, cardiac output increased from 3.6 +/- 0.5 to 3.7 +/- 0.4 l/min (p < 0.05), and in four patients with EF less than 55%, it increased from 2.9 +/- 0.4 to 3.0 +/- 0.4 l/min (p < 0.01). Cardiac function was improved by right ventricular outflow pacing compared to right ventricular apex pacing regardless of the pacing mode or cardiac function.

Left ventricular lesions in arrhythmogenic right ventricular dysplasia have not been well described, and the relationship between the left ventricular lesions and the 12-lead electrocardiographic findings has not been analyzed. This study examined whether the presence of left ventricular lesions and the extent of right ventricular lesions due to arrhythmogenic right ventricular dysplasia are predictable by 12-lead electrocardiographic findings. The 12-lead electrocardiograms during sinus rhythm and left and right ventriculography were studied in 29 patients (27 males and 2 females, mean age 42.6 +/- 15.5 years) diagnosed by the current criteria for this disease. After evaluation, patients were divided into two groups: those with normal left ventricles (normal group) and those with left ventricular wall motion abnormalities (abnormal group). Seventeen of the 29 patients (59%) were classified into the abnormal group. Left ventricular wall motion abnormalities were located in the posterolateral (4 patients), apical (1), and posterolateral and apical regions (12). QS patterns of abnormal Q waves in lead I, aVL or V5, V6 rS patterns (R/S ratio < 1) in leads I and V6, and/or R or Rs patterns (R/S ratio > 1) in lead V1 were observed in all patients in the abnormal group, but in none in the normal group. There was a positive correlation between the right ventricular end-diastolic volume index and the number of precordial negative T waves (r = 0.746, p < 0.0001), and the time from onset of the QRS to the terminal portion of the epsilon wave in lead V1 (r = 0.627, p < 0.001). The correlation coefficients showed no significant differences between the groups. A left ventricular lesion associated with arrhythmogenic right ventricular dysplasia was not unusual (59%), and our study suggests that the posterolateral and apical regions are the most frequent sites. The presence of these lesions were predictable by the QRS abnormalities. Moreover, regardless of the presence of such a lesion, the extent of the right ventricular lesion is also predictable by the 12-lead electrocardiographic findings.

In many patients, right ventricular (RV) dysfunction is due to RV infarction. In some patients, however, RV dysfunction may be secondary to the left ventricular (LV) dysfunction. In order to clarify the influence of poor LV function on RV function, RV ejection fraction (EF) was evaluated serially by thermodilution techniques (REF-1, Edwards Laboratories) in patients with LVEF less than 40% who underwent aorto-coronary bypass surgery with uneventful postoperative course. The patients were divided into four groups depending on the site of LV infarction; anterior (n = 13), inferior (n = 8), anterior + inferior (n = 16), and no infarction (n = 4). Control (n = 11) consisted of the patients with LVEF more than 60% and with no significant stenosis of the right coronary artery. Cardiac index, intracardiac pressures and amount of catecholamine used during postoperative course showed no significant differences among the groups including control. However, the groups except for the group of anterior infarction showed significantly low pre- and postoperative RVEF compared with control. Only the group of anterior infarction had almost normal RVEF. These results mean that RV dysfunction associated with inferior infarction remain long afterwards and that low LVEF due to anterior infarction caused little effect on RV function.

The right ventricular dP/dtmax and relatively load-independent index, dP/dtmax/IP (IP: instantaneous pressure difference between the right ventricle and right atrium) can be measured from the tricuspid regurgitant velocity by continuous-wave Doppler echocardiography. The present study investigated these indices as measures of right ventricular contractility. Thirty-one patients were classified into three groups: 11 patients without right ventricular disease (control group), 9 with dilated cardiomyopathy and 1 with hypertrophic cardiomyopathy in the dilated phase (DCM group), and 10 with pulmonary hypertension (PH group). Right ventricular contractility was impaired in both the PH group and DCM group, but dP/dtmax was significantly larger in the PH group compared with the control group and DCM group (519 +/- 113 vs 249 +/- 66 and 234 +/- 78 mmHg/sec, p < 0.01). There was no significant difference between dP/dtmax in the control group and DCM group. dP/dtmax/IP in the PH group was smaller than the control group (31 +/- 8 vs 39 +/- 7/sec, p < 0.05) and larger than the DCM group (22 +/- 12/sec, p < 0.05). Mean New York Heart Association grading was 1.0 in the control group, 3.1 in the DCM group, and 2.8 in the PH group, respectively. Thus, dP/dtmax/IP, noninvasively obtained by continuous-wave Doppler echocardiography, may be a better index for evaluating right ventricular contractility than dP/dtmax.

Although 99mTc-pyrophosphate (PYP) myocardial scintigraphy has so far been widely used for the diagnosis of right ventricular infarction, PYP accumulation disappears within one week or so. To evaluate the myocardial condition of the right ventricle alternatively, myocardial SPECT with 99mTc-MIBI was performed in 16 patients with acute inferior left ventricular infarction, and ECG-gated myocardial SPECT data acquisition was accompanied in 14 of 16 patients. Right ventricular perfusion defect was observed in 4 of 16 patients (RVI (+) group), and the remains were negative (RVI (-) group). Then, right ventricular count increase rate (RV %WT) of MIBI from end-diastole to end-systole was calculated using an automated method which was developed for quantification of wall thickening in our laboratory. The RV %WT was conceived to be an objective index representing right ventricular contractility. RVI (+) group (n = 3) as compared with RVI (-) group (n = 11) had significant lower RV %WT (26.7 +/- 3.2 vs. 49.6 +/- 14.2; p < 0.01). In conclusion, ECG-gated myocardial SPECT with MIBI was considered to be useful for assessment of myocardial perfusion and contractility of right ventricle.

The usefulness of magnetic resonance imaging (MRI) for estimating right ventricular function and the influence of left ventricular dysfunction on the performance of the right ventricle were assessed in 43 patients with chronic myocardial infarction (MI) and 14 control subjects (N) using electrocardiography-gated MRI and cardiac catheterization. Patients with MI were divided into three groups according to the location of the coronary lesions; 22 patients with left coronary artery lesion (LCA group), 13 with right coronary artery lesion (RCA group), and 8 with both left and right coronary artery lesions (L+R group). The right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF) were measured by Simpson's rule algorithm on transverse images of the right ventricle obtained at the end-systolic and end-diastolic phases. In 34 of the 43 patients, the same parameters of right ventricular function were calculated by the thermodilution method using a Swan-Ganz catheter with rapid response thermistor. Left ventricular ejection fraction (LVEF) and end-diastolic volume were determined from left ventriculography. The intraobserver reproducibility (11 cases, r = 0.97) and interobserver reproducibility (11 cases, r = 0.92) of RVEF measured by MRI were excellent. The RVEF and RVEDV determined from MRI were significantly correlated with those from the thermodilution method (RVEF: r = 0.56, RVEDV: r = 0.52). There was no difference in right ventricular end-diastolic volume index in any patient group. The RVEF was decreased in the L+R (41.0 +/- 4.5%, p < 0.01) and RCA (45.9 +/- 6.6%) groups, but there was no difference between the LCA (50.6 +/- 6.6%) and N (48.9 +/- 4.3%) groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Unlabelled: The purpose of this experimental study is to evaluate the efficacy of linear-type right ventricular (RV) dynamic cardiomyoplasty in a setting of patch enlargement model for hypoplastic RV. In 6 puppies (6-8 kg), under a cardiopulmonary bypass (CPB), RV free wall and septal traveculation were resected and replaced with large pericardial patch, simulating RV patch enlargement of hypoplastic RV. A pedicled left LD, anchored to 3rd rib, wrapped onto the RV patch in parallel to RV long axis, while LD fixed to only RV diaphragma surface without wrapping LV surface. After the termination of CPB, LD flap was synchronously paced at 1:1 ratio with cardiac beat with a trained-pulse stimuli (10-25 Hz). RV performance was tested by RV function curve (RVSWI vs CVP) and RV pressure-volume relationship (ESPVR) assessed by conductance catheter., Results: LD graft stimuration showed significant augmentation of PAP (145 +/- 21%), PA flow (152 +/- 21%) and AP (128 +/- 23%) at CVP of 10 mmHg. RV function curve and ESPVR confirmed dramatical augmentation of RV performance by graft stimulation, which was identical to preoperative normal RV function even at the low CVP range., Conclusions: Linear LD myoplasty after patch enlargement of RV may viable surgical option for hypoplastic RV.

This study was undertaken to compare postsurgical right ventricular function and the occurrence of conduction disturbances after employing cold blood antegrade or retrograde cardioplegia during open heart surgery. Thirty-four patients were divided into AC (antegrade) and RC (retrograde) groups for the difference of route for delivery of cardioplegic solutions. Preoperative evaluation of cardiac and respiratory function revealed to be equal characteristics between the groups. Postoperatively, A-aDO2 and respiratory index (RI) as functional parameters of oxygenation capacity, LVSWI, RVSWI, dosage of dopamine and conduction disturbances were monitored at 0, 3, 6, 12 hours after termination of cardiopulmonary bypass and at extubation period. Although the recovery of respiratory function and left ventricular function were similar in both groups, temporal suppression of right ventricular function was indicated in RC group during early period after surgery, and then recovered to the same values of AC group within 3 hours. In RC group, several type of conduction disturbances were detected in 28 per cent of patients. But none of the persistent conduction disturbances were remained in all patients. We suggest retrograde coronary sinus perfusion may emerge as a valuable alternative to antegrade methods for delivery of cardioplegia.

Body surface isopotential T map was analyzed to detect right ventricular volume and pressure overloads in 25 patients with secundum atrial septal defect. Three patterns were distinguished: the T map resembling normal (type A, n = 9); that with isolated negative area in positive area (type B, n = 11); and that with rightward movement of maximum (type C, n = 5). Right ventricular end-diastolic volumes in type B (161 +/- 19% of normal; %N) and C (175 +/- 40% N) were significantly (p < 0.01) greater than those in control (100 +/- 9% N) and type A (113 +/- 18% N). Right ventricular systolic pressure in type C (48 +/- 11 mmHg) was significantly (p < 0.01) higher than those in control (30 +/- 5 mmHg), type A (31 +/- 4 mmHg) and type B (34 +/- 5 mmHg). These results suggest that the cases with type B have right ventricular volume overload, and those with type C have both volume and pressure overloads.

One and one half ventricle repair consisting of the Glenn operation and the right ventricular outflow tract reconstruction was performed in a 4-year-old boy. The diagnosis of this patient was pure pulmonary atresia. He had undergone Brock's operation, Blalock-Taussig shunt and a central shunt at neonatal period. At the time of one and one half ventricle repair, the connection between the superior vena cava and the right atrium was left open. Although the RVEDV was 34.3% of normal, the topology of the right ventricle was tripartite. At three months after one and one half ventricle repair, RVEDV increased up to 52.7% of normal. This data suggests that a further definitive surgery, i.e., complete biventricular repair could be applicable in the future.

We investigated right ventricular function during left heart bypass (LHB) with 18 mongrel open-chest dogs, in normal and acute heart failure (AHF) dogs which underwent aortic cross clamp. Left ventricular unloading was completely accomplished with a centrifugal pump. For more accurate evaluation of right ventricular volume, conductance catheter was employed to assess right ventricular function. Analysis were performed with right ventricular pressure-volume curve which was changed by transient volume loading on right ventricle. And right ventricular properties with and without LHB were compared by the use of load independent parameters as follows. Right ventricular systolic property was evaluated by maximum elastance (Emax) and stroke work-end-diastolic volume relation (SW/EDVR), and its diastolic function was evaluated by end-diastolic pressure-volume relation (EDP/VR). Overall right ventricular performance was assessed by stroke work-end-diastolic pressure relationship (SW/EDPR). In the normal heart, only a parallel shift to the right in EDP/VR and SW/EDVR was noted without any significant changes in slope with LHB. On the other hand, in AHF dogs, the slope of SW/EDVR and SW/EDPR were increased from 0.14 +/- 0.08 to 0.18 +/- 0.08 (p < 0.05), from 0.22 +/- 0.15 to 0.34 +/- 0.19 (p < 0.01), respectively, and the curve of EDP/VR was shifted right and downward. These result suggested that decompression of the left ventricle and septal shifting by LHB provided good diastolic compliance and afterload unloading of the right ventricle, and these effects had a more significant role in acute heart failure than in the normal heart.

Postoperative right ventricular function was evaluated serially by thermodilution techniques (REF-1, Edwards Laboratories) in patients who underwent aorto-coronary bypass surgery with uneventful postoperative recovery. The patients were divided into three groups depending on the location of critical stenosis of the right coronary artery. The stenosis was proximal to the right ventricular branch in group I (n = 13), distal to the right ventricular branch but proximal to the acute marginal branch in group II (n = 13) and distal to the acute marginal branch in group III (n = 11). Control (n = 20) consisted of the patients with no significant stenosis of the right coronary artery. Cardiac index, intracardiac pressures and amount of cathecolamin used during postoperative course showed no significant differences among the groups including control. With the use of cathecolamine after surgery, right ventricular ejection fraction (RVEF) rose and right ventricular volumes (RVEDV and RVESV) decreased in all the groups except for group I. These values in group I were unchanged. Thus, there were significant differences in RVEF, RVEDV and RVESV between group I and control. These results mean that right ventricular dysfunction may remain even long after occlusion of the proximal right coronary artery.

We operated on a 47-year-old male for Tetralogy of Fallot with severe right heart dysfunction (RVEF 25%, RVEDP 15 mmHg, massive TR) and right heart failure (ascites and edema). The operation was completed successfully. However, persistent severe arrhythmia occurred in the CCU and assisted circulation was used for 6 days until the patient's condition stabilized. Arrhythmia diminished and hemodynamic status improved gradually. The patient improved sufficiently to be able to eat and read books. Unfortunately, he died of sudden ventricular arrhythmia on 69 POD. It was suspected that the right ventricle in this case had deteriorated beyond the threshold for surviving the radical operation for Tetralogy of Fallot.

To study the effect of location of coronary artery lesions on right ventricular (RV) function, exercise 81mKr multiple gated equilibrium scintigraphy was performed in 35 cases with coronary artery disease and 12 control subjects. Thirty five patients were divided into three groups: group I; those without right coronary artery (RCA) stenosis (n = 16), group II; those with stenosis of RCA distal to the origin of the major RV branch (n = 8) and group III; those with proximal RCA stenosis (n = 11). RV ejection fraction (RVEF) at rest was not significantly different among four groups. However, increase of RVEF during supine bicycle exercise was markedly suppressed in group III compared with any other three groups. Abnormal RVEF response to exercise was seen in all 11 cases of group III and five of eight cases of group II, while only two of 16 cases of group I showed abnormal RVEF response. Five of seven cases who demonstrated abnormal RVEF response without proximal RCA stenosis had multiple coronary vessel disease. On the other hand, the left ventricular (LV) response was more suppressed in group II than in group III, and no significant correlation was observed between RVEF and LVEF responses during exercise. The impairment of RVEF response to exercise seemed to be related to the proximal RCA stenosis. However, in the presence of multiple coronary vessel disease, increased RV afterload during exercise may also play a role in abnormal RVEF response in coronary artery disease.

We performed unilateral pulmonary arterial occlusion test (UPAO) for the preoperative evaluation of lung function in patients undergoing lung resection. In this test, the main pulmonary artery of either side is occluded to simulate postoperative functional status. In order to evaluate the right ventricular hemodynamic function, we measured right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) throughout UPAO by thermodilution method. We investigated the relationships between changes in right ventricular hemodynamic function and postoperative complications related to cardiac functions, namely arrhythmias or heart failure. Thirty-four patients without heart disease prior to lung resection were examined by UPAO, and RVEF and RVEDVI were measured. Analyses demonstrated that changes in RVEF were inversely correlated with changes in RVEDVI. In 6 cases, RVEDVI increased from control by over 20% during UPAO. All of these patients had postoperative cardiac complications. The hypothetical ventricular function curves showed a large increase in RVEDVI relative to right ventricular stroke work index (RVSWI), suggesting a decrease in right ventricular function. In conclusion, these results suggest that changes in RVEDVI during UPAO may predict postoperative cardiac complications in patients undergoing pulmonary resection.

A 43-year-old male diagnosed as constrictive pericarditis with dyspnea, fatigability and substantial pericardial calcification on chest roentgenogram underwent pericardiectomy through median sternotomy. The heavily calcified pericardium which was adherent to the anterior and diaphragmatic surface of the heart was successfully resected by the combined use of ultrasonic surgical aspirator (CUSA) and argon beam coagulator (ABC). Intraoperative bleeding was minimal because the adhesion between the pericardium and myocardium, coronary arteries or inferior vena cava were easily dissected with CUSA. Intraoperative hemostasis was also satisfactory with ABC. Perioperative measurements of right ventricular ejection fraction were also effective in evaluating the right ventricular function.

Recently it is claimed that the drainage procedure may be a useful method for giant pulmonary bulla in compromised patients. We reported the anesthetic managements of three patients with giant bulla for these procedures. We chose epidural anesthesia in order to prepare for the postoperative analgesia and the expansion of surgical procedure. In selecting circulatory support method, care was taken to choose dobutamine that would cause no suppression of hypoxic ventilatory drive. There is no doubt that right ventricular function is particularly important in patients with chronic obstructive lung disease. We measured right ventricular ejection fraction by thermodilution method and end-tidal CO2 by nasal cannula. These measurements may be useful methods for perioperative monitoring.

Clinical usefulness of quantitative analysis of right ventricular overloading was evaluated by 201Tl myocardial SPECT in comparison with cardiac catheterization and MRI. Seventy-four MBq of 201TlCl was intravenous injected and 201Tl myocardial SPECT was performed on 40 patients (mean age: 61.0 +/- 11.8) with right ventricular overloading. Regions of interest (ROI) were selected on right and left ventricular walls in a midventricular short axis image of SPECT and uptake of each ROI were counted. The right ventricle (RV)/left ventricle (LV) 201Tl uptake ratio (R/L-Tl) was calculated. Wall thickness of RV and LV were measured on MRI and the RV/LV wall thickness ratio (R/L-WT) was calculated. RV and LV pressure were recorded in cardiac catheterization, and the RV/LV systolic pressure ratio (R/L-P) was calculated. There was significant positive correlation (Y = 0.73X + 0.19, r = 0.71, p < 0.001) between R/L-Tl and R/L-WT. R/L-Tl was positively correlated with R/L-P in patients with pressure overload (Y = 1.14X - 0.049, r = 0.85, p < 0.001) and in patients with volume overload (Y = 0.51X + 0.023, r = 0.88, p < 0.001) and the slope of the regression line in patients with pressure overload was significantly steeper than that in patients with volume overload (p < 0.001). In conclusion, quantitative analysis of right ventricular overload by 201Tl myocardial SPECT is useful to estimate RV/LV wall thickness ratio and pressure ratio.

In order to assess the efficacy and the problems of right ventricular (RV) assist in supporting the failing RV, we analyzed the influence of RV assist on pulmonary circulation, respiratory function and left ventricular (LV) function in dogs. Thirty healthy mongrel dogs were anesthetized with thiopental sodium. The animals were intubated and ventilated with 100% oxygen. Tidal volume was 15 ml/kg at a rate of 20 per minute. RV failure was produced by ligation of the right coronary artery at its origin and the mid-portion. Tricuspid regurgitation was induced by tearing the chordae tendineae with a specially made knife, while 5M-NaOH was injected into the RV free wall. Then, RV support was initiated by placing a drainage cannula in the right atrium and a perfusion cannula in the pulmonary artery trunk. The RV assist was done with a diaphragm type pneumatic pump, which worked in ECG asynchronous mode (% systole:40%, 100 beats per minute). Animals were divided into three groups according to RV assist rate; Group I: 30% (n = 10), Group II: 60% (n = 10), Group III: 100% (n = 10). Hemodynamics were observed for five hours and measured once an hour. Hemodynamically, there were no significant differences in mean right atrial pressure, pulmonary artery pressure or aortic pressure at any time for the three groups. In terms of net infiltration pressure, given by the formula, pulmonary microvascular pressure minus colloid osmotic pressure, a significant difference appeared early, at the 1st hour, between Groups I and III (P < 0.01), and lasted until the 5th hour. Alveolar-arterial oxygen differences were highest in Group III and lowest in Group I throughout most of the experiment. Early on, at the 1st hour, a significant difference of Alveolar-arterial oxygen difference developed between Groups I and III (p < 0.01) and at the 2nd hour a significant difference was also seen between Groups II and III (p < 0.05). Extravascular lung water was 8.9 +/- 2.2 ml/kg at the 5th hour in Group III, which was significantly higher than that in Groups I and II (p < 0.01), which were 6.1 +/- 1.3 and 6.1 +/- 1.1 ml/kg. LV max. dp/dt at the 5th hour in Group III was significantly lower than that in Groups I and II (p < 0.05). Postmortem histopathologic examination showed a high degree of perivascular cuffing in Group III, slight cuffing in Group II, and almost none in Group I and the control group. There was no alveolar flooding in any group.(ABSTRACT TRUNCATED AT 400 WORDS)

Echocardiography can measure various parameters of left and right ventricle function during either systolic or diastolic phase. Many parameters of cardiac function are obtained by B-mode, M-mode and Doppler images. Recently, invasive techniques, such as trans-esophageal echography, intra-luminal echography, contrast echography of the left ventricular muscle and stress echography were developed. In the future, 3-dimensional echography and acoustic tissue characterization will be developed for quantitative measurement of cardiac functions.

We report a seven-year-old boy who underwent a successful Jatene procedure seven years after Senning procedure. The modified Senning operation was performed for the treatment of transposition of the great arteries with intact ventricular septum at three years of age. However, he gradually showed the progressive right ventricular failure with tricuspid regurgitation after operation. When he was referred to our hospital, he was in severe right ventricular failure and showed massive tricuspid regurgitation simultaneously with the moderate degree of left ventricular failure. Staged pulmonary artery banding was applied to prepare the left ventricle for Jatene procedure in spite of the presence of left ventricular failure. The systolic pressure ratio of left ventricle to right ventricle was elevated to 0.91 by this banding although the left ventricular ejection fraction decreased from 43% to 30%. And Jatene procedure was successfully performed after three months of preparation period. Catheterization study after Jatene procedure revealed improved right and left ventricular functions with decrease of tricuspid regurgitation. We conclude that the Jatene procedure should be an ideal alternative in patient with right ventricular failure and/or tricuspid regurgitation after an atrial switch operation; the left ventricle could be prepared by an effective pulmonary banding in most instances.

We have successfully performed a two-stage Jatene procedure in four patients who showed severe anatomical right ventricular dysfunction after atrial switch (Mustard or Senning) operation for transposition of the great arteries. All four patients developed an adequate left ventricular pressure for the arterial switch operation by one or two-stage pulmonary artery banding. Left ventricular posterior wall thickness increased sufficiently enough after the banding although left ventricular ejection fraction showed significant decrease. After Jatene procedure left ventricular ejection fraction recovered, and RV end-diastolic volume which had been prominently enlarged preoperatively was dramatically normalized. Cardiac index increased from 3.6 +/- 1.6 l/min/m2 preoperatively to 5.3 +/- 6.1 l/min/m2 postoperatively with the decrease in left atrial pressure. Postoperative electrophysiological study revealed the recovery of sinus node function and atrial conduction by means of the take-down of atrial switch operation previously performed. We conclude that the Jatene procedure should be an ideal alternative in patients with right ventricular dysfunction after atrial switch operation. The left ventricle could be prepared by an effective pulmonary artery banding in most instances.

Right ventricular function was assessed using gated blood pool single photon emission computed tomography (GSPECT) in 10 normal subjects and 14 patients with inferior myocardial infarction. Three-dimensional background subtraction was achieved by applying an optimal cut off level. The patient group consisted of 6 patients with definite hemodynamic abnormalities indicative of right ventricular infarction (RVI) and 8 other patients with significant obstructive lesion at the proximal portion of right coronary artery without obvious hemodynamic signs of RVI. Right ventricular regional wall motion abnormalities were demonstrated on GSPECT functional images and the indices of right ventricular function (i.e. the right ventricular ejection fraction (RVEF), the right ventricular peak ejection rate (RVPER) and the right ventricular peak filling rate (RVPFR)) were significantly reduced in the patient group, not only in the patients with definite RVI but also in those without hemodynamic signs of RVI. The present study indicates that inferior infarction is frequently associated with RVI, even in the absence of definite hemodynamic signs, when the proximal portion of right coronary artery is obstructed. It is concluded that GSPECT is reliable for the assessment of right ventricular function and regional wall motion, and is also useful for the diagnosis of RVI.

Relationships between biventricular pressures, left ventricular shape and paradoxical septal motion in patients with right ventricular pressure overload (RVPO) are unknown. To clarify these relationships, we measured left and right ventricular short-axis dimensions and ventricular pressures using anesthetized open-chest dogs with pulmonary embolizations. With repeated microembolization, right ventricular systolic pressure (RVSP) increased stepwise from a level of 27 mmHg to the maximum value of 72 mmHg. This elevation caused gradual leftward shift of the interventricular septum (IVS) both at end-diastole and end-systole. Further embolization caused collapse (shock: left ventricular systolic pressure: LVSP < 70 mmHg) with a fall in RVSP. In the state of shock, the rise in right ventricular end-diastolic pressure (RVEDP) and fall in left ventricular end-diastolic pressure (LVEDP) were prominent, and the degree of shift of the IVS became significantly greater at end-diastole than at end-systole, resulting in paradoxical motion of the IVS. There were significant linear relationships between the degree of end-diastolic IVS displacement and end-diastolic transseptal pressure (LVEDP-RVEDP), and between the degree of end-systolic IVS displacement and end-systolic transseptal pressure (LVESP-RVESP) throughout the course of repeated pulmonary microembolization even in the state of shock. In conclusion, abnormal movements of the IVS in RVPO patients indicate the presence of a marked decrease in end-diastolic transseptal pressure due to right ventricular failure.

To investigate the influence of atrioventricular asynchronous contraction on left and right ventricular performance, pulsed Doppler echocardiographic studies were performed in 10 patients who received permanent pacemaker (VVI mode), but without significant heart disease except for complete heart block. After setting the pacing rate at 40 per min, the performance was analyzed during the patient's own slow ventricular rate. Flow velocity patterns at the left (LVOT) and right ventricular outflow tracts (RVOT) were recorded by pulsed Doppler echocardiography, and ejection time (EjT), acceleration time (AcT), peak velocity (PV) and flow velocity integral (FVI), which is proportional to stroke volume, were measured for each outflow tract. When the patient's own atrial contraction occurred during ventricular systole, EjT, AcT, PV and FVI of flow at the LVOT and EjT, AcT and FVI of flow at the RVOT were decreased. Percent change of the FVI of flow at the RVOT (-34.6%) was significantly greater than that of flow at the LVOT (-16.2%, p < 0.01). These results indicate that the loss of right ventricular performance might play a prominent role in the genesis of the hemodynamic deterioration with atrioventricular asynchronous contraction.

The effect of aging on cardiac function in patients with right bundle branch block (RBBB) was commonly unknown, so left ventricular function and right ventricular function were investigated, using first-pass radionuclide angiography. Twenty-six patients with RBBB and 28 normal subjects were studied at rest and during bicycle exercise. Patients with RBBB but normal cardiovascular systems aged 33 to 75 years were divided into those within 60 years (n = 17) and those over 65 years (n = 9). Using the same method, normal subjects aged 38 to 83 years were divided into those within 60 years (n = 18) and those over 65 years (n = 10). Mean age between normal subjects and patients with RBBB didn't differ significantly. The response of left ventricular ejection fraction in normal groups rose during exercise, but its exercise tolerance function declined with aging. Left ventricular diastolic filling in normal groups declined at rest and during exercise with aging. Left ventricular function in RBBB groups showed the same results as those of normal groups. The response of right ventricular ejection fraction and its exercise tolerance function in normal groups was not influenced by aging. However, in contrast, right ventricular function in RBBB groups decreased with aging. We suggest that the mechanism of decrease of right ventricular function in aging patients with RBBB may be caused by the change of right ventricular contraction which is affected by the aging process.

To assess the prognostic significance of right ventricular function in dilated cardiomyopathy (DCM), we studied consecutive 57 DCM patients. There were 41 men and 16 women, whose mean age was 48 ys. (range 3-68 ys.). The mean LVEF in all patients was 29 +/- 11%, and the mean interval from the onset of symptom of cardiac failure (CHF history) was 4 ys. (range 0-33 ys.). With follow-up of 3.8 ys., five patients had died until the first year, and 14 had died until the third year. By using multivariate regression analysis, there were no prognostic significance in clinical parameters such as age, CHF history, sex, atrial fibrillation, except for NYHA class, and medication at the third year. In survival curves according to Kaplan-Meier method, RVEF and mean PA had predictive value (p less than 0.05), while LVEF did not. The patients with RVEF less than 45% had poor survival rate compared to those with RVEF greater than or equal to 45%. The patients with RVEF less than 45% showed lower LVEF and LVESVI. RVEF may offer prognostic predictive value through the effect of not only mean PA but also left ventricular parameter. In conclusion, radionuclide assessment of right ventricular function should be valuable for the prognostic evaluation of DCM patients.

The purpose of this study is to assess the right atrial and ventricular function by radionuclide ventriculography using continuous infusion of 81mKr in normal subjects and in patients with heart disease. 1) Reproducibility of RVEF measurement by continuous infusion of 81mKr was good (interobserver; gamma = 0.97, p less than 0.001, n = 20: intraobserver; gamma = 0.97, p less than 0.001, n = 20). This method had a excellent correlation with RVEF of 99mTc first-pass technique (gamma = 0.92, p less than 0.001, n = 20). 2) RVEF was measured in 10 normal volunteers, 76 patients with myocardial infarction (OMI), 20 patients with dilated cardiomyopathy (DCM), 5 patients with arrhythmogenic right ventricular dysplasia (ARVD) and 5 patients with primary pulmonary hypertension (PPH). In OMI and DCM, their RVEF was lower than that of normal volunteers and, in ARVD and PPH, lower than that of OMI and DCM. There was a significant inverse correlation between RVEF, mean pulmonary artery pressure and right ventricular end-diastolic volume index. 3) The effect of the location of right coronary artery (RCA) lesions on RVEF during exercise was also evaluated. Ten normal volunteers and 27 patients with OMI were studied at rest and during exercise. The patients with OMI were divided into two groups: those without proximal RCA lesions (non RCA group, n = 12) and those with proximal RCA lesions (RCA group, n = 15). Although there were no significant increases of RVEF during exercise in both group, the percent change in RVEF was less in RCA group than in non RCA group. These findings suggested that proximal RCA stenosis is a major determinant of exercise RVEF. 4) To assess the right atrial function, right atrial volume curve was measured in 10 normal volunteers, 32 patients with OMI and 4 patients with PPH. The curve was clearly divided into 4 phase; filling phase (312 +/- 40 msec), early ejection phase (276 +/- 53 msec), plateau an index of right atrial reservoir function, was 0.41 +/- 0.05 and Contractile Volume/Stroke Volume (Contr. V/SV), as an index of right atrial pump function, was 0.23 +/- 0.05 in normal volunteers. In OMI and PPH, atrial reservoir function decreased and atrial pump function increased. It was concluded that radionuclide ventriculography using continuous infusion of 81mKr was useful to assess the right heart function.

Right ventricular function at rest and during exercise was studied in 33 patients with mitral valve disease by equilibrium gated radionuclide angiography using 99mTc in vivo labeled red blood cells. Radionuclide measurements of right ventricular ejection fraction (RVEF) were correlated with mean pulmonary arterial pressure (mPAP). RVEF decreased significantly with exercise. There was no significant correlation between RVEF at rest and mPAP. However, mPAP showed significant negative correlation with RVEF during exercise and with the changes of RVEF from rest to exercise. It is concluded that RVEF during exercise in mitral valve disease is affected by right ventricular afterload, and the measurements of RVEF at rest and during exercise by equilibrium gated radionuclide angiography is useful to assess right ventricular afterload.

We were able to diagnose right ventricular infarction (RVI) by transesophageal echocardiography (TEE) in a patient with acute inferior infarction, and it was confirmed by cardiac catheterization. To evaluate right ventricular (RV) function quantitatively, area shortening (AS) and regional AS (rAS) were measured from RV images obtained by TEE. The AS correlated with RV ejection fraction obtained by radionuclide angiography (r = 0.72). The patient with RVI showed depressed RV function by AS measurement with decreased rASs of all regions in the acute phase. In the chronic phase, RV function of the patient improved, especially in the region of the ventricular septum and apex regions. These results indicate availability of TEE and that RV function can be evaluated by TEE.

The right ventricular ejection fraction (RVEF) is an objective evaluation of the right ventricular systolic function. Recently a rapid-response thermister pulmonary artery catheter which measures RVEF and stroke volume (SV) was introduced. With this new method, RVEF and the right ventricular volumes (RVV) were measured in patients with chronic pulmonary diseases (CPD) and normal subjects. In addition, to evaluate the validity of this method, the data was compared with Kr81m perfusion method. The RVEF and the RVV of CPD patients were also compared with pulmonary hemodynamic data. There was a good correlation between the RVEFs obtained by the Kr81m perfusion method and the TD method. (r = 0.71, p less than 0.001). There was a tendency towards a low RVEF in patient with CPD with pulmonary hypertension (PAm greater than 20 mmHg) or high pulmonary vascular resistance (PAR greater than 160 dyne/sec/cm-5) and the RVV increased in the same group. These results suggested that the right ventricle was unable to respond to the increase of afterload in the CPD group and the evaluation of RVEF and RVV in patients with CPD using the new TD method was valuable for assessing the right ventricular function.

Two-dimensional echocardiography and Doppler echocardiography were performed in 19 patients with Duchenne muscular dystrophy for evaluating right ventricular overload and left ventricular function. Five of 19 patients were treated with mechanical ventilation. We defined right ventricular overload as right ventricular enlargement and the presence of paradoxical ventricular septal motion. The right ventricular dimensions in patients with mechanical ventilation were significantly larger than in patients without mechanical ventilation (p less than 0.01). All the patients with and without mechanical ventilation showed no significant right ventricular enlargement and none of them showed paradoxical ventricular septal motion. As for left ventricular function, there were no significant differences in the incidence of regional or diffuse wall motion abnormalities between two groups. However, the left ventricular fractional shortening was significantly lower in patients with mechanical ventilation than in patients without it (p less than 0.05), and the incidence of mitral regurgitation was significantly higher in the former than in the latter (p less than 0.01). Our findings suggest that right ventricular function is preserved even in patients with respiratory failure by appropriate respiratory treatment. Therefore, we should give attention to the progression of left ventricular dysfunction in long term prognosis.

Recently, coronary artery bypass grafting operations for patients with total proximal multi-vessel coronary obstructions are increased. In these cases, antegrade cardioplegia through the aortic root has been applied as usual. But it seems to be difficult to deliver cardioplegic solution to myocardium uniformly beyond coronary stenosis. Retrograde coronary sinus cardioplegia in the presence of proximal coronary artery obstruction could maintain improved cardioplegic delivery and satisfactory myocardial protection. Because of the limitation of antegrade cardioplegia, retrograde cardioplegic technique has, once again, been cited as a reasonable alternative to antegrade cardioplegia. But on the other hand, retrograde cardioplegia includes the potential for relatively inadequate preservation of right ventricle based on the venous drainage communication to the coronary sinus. The object of the present work is mainly to evaluate the efficacy of retrograde coronary sinus cardioplegic technique for right ventricle by electrophysiological method. Thirty-six adult mongrel dogs divided three groups. Sixteen animals (Group I) received GIK cardioplegia through the coronary sinus, thirteen animals (Group II) received GIK added diltiazem cardioplegia through the same way, and seven animals (Group III) received GIK cardioplegia through aortic root. No large temperature gradients of myocardium between right and left ventricle in each group and also temperature gradients of right ventricle between three groups have been observed. The time duration from starting of injection of cardioplegia to disappear the electrical activity in right and left ventricle were 11.4 +/- 8.2, 3.4 +/- 1.2 minutes in group I, 2.9 +/- 1.5, 2.2 +/- 1.4 minutes in group II, and 0.9 +/- 0.4, 0.9 +/- 0.2 minutes in group III. The time duration from starting of injection of cardioplegia to reappear the electrical activity in right and left ventricle were 6.4 +/- 8.7, 13.4 +/- 7.9 minutes in group I, 20.0 +/- 3.5, 21.3 +/- 1.6 minutes in group II and 18.0 +/- 5.5, 18.7 +/- 4.5 minutes in group III. Unipolar peak-to-peak amplitude (UPPA) analysis reveals the condition of myocardial preservation during ischemic arrest and we compared preischemic UPPA with post-ischemic UPPA. In group I, UPPA declined of 44.1 +/- 29.3% in right ventricle and 72.7 +/- 27.6% in left ventricle, in group II, 78.7 +/- 28.7%, 81.9 +/- 23.6%, in group III, 71.4 +/- 18.7%, 76.7 +/- 9.89%. Analysis of ultrastructural changes in the myocardium are shown that injury was most manifest in the right ventricle of group I, but in group II, ultrastructure of right ventricle maintained nearly normal condition.(ABSTRACT TRUNCATED AT 400 WORDS)

A 67-year-old woman underwent CABG because of severe triple vessel disease. She could not wean from CPB in spite of full inotropic drugs and IABP support due to right ventricular failure probably caused by the perioperative right ventricular infarction. Right heart bypass (RHB) with a centrifugal pump was used. Finally she could wean from CPB and took an uneventful postoperative course except mediastinitis. During 5 days of RHB operation ACT was maintained between 180s and 200s by systemic heparinization. RHB with a centrifugal pump is a reliable method to assist a failing right ventricle.