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We report a 17-year-old man presented with palpitation. Echocardiography demonstrated secundum atrial septal defect (ASD) with marked right sided dilatation, indicating significant left to right intracardiac shunting. Cardiac magnetic resonance imaging performed 3 months after transcatheter ASD closure demonstrated marked improvement in biventricular systolic function.
Two-dimensional echocardiography was applied in 10 closed-chest dogs to evaluate, in several left ventricular (LV) short-axis cross sections and subsegments, the regional contractile response to right atrial pacing. Compared with sinus rhythm (81 +/- 10 beats/min), which exhibited a moderate 7.2 +/- 12.0% (mean +/- standard deviation) base-to-apex increment in function, this gradient was significantly augmented to 34 +/- 12% by pacing at a heart rate of 180 beats/min. Measurements of wall thickening and perimeter shortening exhibited similar trends. Differences also were observed in subsegments of individual cross sections: in sinus rhythm the base-to-apex difference in function was relatively minor in the anterior and lateral aspects of the left ventricle (-9.1 +/- 18% and -1.9 +/- 19%), whereas a significant increase was noted in posterior and midseptal zones (18 +/- 17% and 22 +/- 30%). In response to pacing, the anterior and lateral wall base-to-apex gradients were significantly augmented (25 +/- 8% and 35 +/- 34%), but there was no further change in the posterior or septal regions. In conclusion, apical regions of the canine left ventricle responded to right atrial pacing with significant augmentation of contractile function, whereas more basal levels showed little response. Circumferentially, response to atrial pacing was most pronounced in the anterior and lateral segments.
The results of examination of 61 patients suffering from ischemic heart disease are analysed. All were subjected to catheterization of the right and left parts of the heart, left ventriculography, and selective coronarography. Some parameters of intracardiac hemodynamics, including the end diastolic pressure in the left ventricle, were determined. Atrial vectorcardiogram was recorded after I. T. Akulinichev's system (with mV = 100 mm). Comparison of the parameters of the atrial P loop of the vectorcardiogram with the findings of heart catheterization showed a direct dependence between the atrial changes recorded on the vectorcardiogram and the value of the left ventricular end diastolic pressure. Signs of overexertion of the left atrium grow with an increase in the end diastolic pressure. Quantitative dependence between these parameters is demonstrated. When the end diastolic pressure grows higher, overexertion of the left atrium is naturally joined by overexertion of the right atrium. Atrial vectorcardiography may be an important invasive method for appraising the functional condition of the left ventricular myocardium in patients with ischemic heart disease.
Ebstein's anomaly is a rare cardiac malformation that affects the tricuspid valve, right ventricle, and right atrioventricular junction. These anatomical and functional abnormalities cause important tricuspid regurgitation that results in right atrial and right ventricular dilatation and atrial and ventricular arrhythmias. Diagnosis is made by echocardiography. Operation includes tricuspid valve repair or replacement, closure of any interatrial communications, and appropriate antiarrhythmia procedures. Repair of Ebstein's anomaly eliminates right-to-left intracardiac shunting, improves exercise tolerance and functional class, and reduces supraventricular arrhythmias. In addition, quality of life and longevity are improved.
Cardiac function is difficult to assess in patients with atrial fibrillation due to the widely fluctuating cycle lengths resulting in variable ventricular hemodynamics. With respect to ECG-gated blood pool scintigraphy, distortion of the time activity curve occurs due to a summation of irregular cycle lengths. Therefore, performing such a study has been regarded meaningless. To evaluate left ventricular function during atrial fibrillation using scintigraphic technique, a new processing algorithm was devised to make multiple gated images which are discriminated by the preceding R-R interval, and left ventricular filling and function curves were established. The left ventricular filling curve, obtained by plotting end-diastolic volume against the preceding R-R intervals demonstrated an impairment of blood filling in cases of mitral stenosis and constrictive pericarditis, which resolved after mitral commissurotomy in case of mitral stenosis. The left ventricular function curve, established by plotting stroke volume against end-diastolic volume, was analyzed according to indices such as "slope" and "position". Both of these indices were significantly reduced in relation to the severity of heart failure according to the NYHA's functional classification and cardiomegaly on chest radiography. On individual comparisons of underlying diseases, the indices decreased in the following order; lone atrial fibrillation, hyperthyroidism, aging, hypertension, mitral valve disease, ischemic heart disease, dilated cardiomyopathy and aortic regurgitation. The indices correlated closely with ejection fraction. In cases of mitral regurgitation, however, the function curves were situated to the right and above those of lone atrial fibrillation and decreased in slope despite the fairly well-maintained ejection fraction. After treatment with digitalis and/or diuretics, the function curves shifted to the left and upward. In conclusion, left ventricular filling and function curves based on a newly-devised algorithm of ECG-gated blood pool scintigraphy are of considerable clinical value in evaluating cardiac performance in patients with atrial fibrillation. They are widely applicable to the assessment of therapeutic and interventional effects.
Noninvasive assessment of right ventricular (RV) function is important clinically, but current techniques have limitations. Acoustic quantification (AQ) is an automated endocardial border detection technique that allows continuous determination of RV and right atrial (RA) area waveforms and may be useful for the assessment of RA and RV systolic and diastolic performance. Fifty patients (10 normal, 40 with RV pathology) were studied. Signal-averaged RA and RV AQ area waveforms were obtained and analyzed to compute parameters of diastolic and systolic function. All groups demonstrated significant diastolic dysfunction on the RA AQ waveform as manifested by a reduced percentage of passive atrial emptying and increased dependence on active atrial emptying. Abnormalities of diastolic performance were noted in all subgroups on RV AQ analysis as evidenced by a reduction in the percentage of ventricular filling occurring during early diastole and an increased contribution from active atrial contraction. This study demonstrates the feasibility of using automated analysis of signal-averaged RA and RV area waveforms for the evaluation of RV systolic and diastolic performance. This technique identified significant systolic and diastolic dysfunction in four groups of commonly seen right heart pathologies including biventricular heart failure, pulmonary hypertension, pressure and volume overloaded RVs, and biventricular hypertrophy.
The incidence of sudden death in the Wolff-Parkinson-White (WPW) syndrome is not well documented and probably underestimated. This retrospective study concerned 28 consecutive patients presenting with ventricular fibrillation either spontaneously (20) or during electrophysiological investigation (8) but whose characteristics allowed them to be assimilated into a single group. Their clinical and electrophysiological characteristics were compared with those of 60 consecutive patients with the WPW syndrome who had documented atrial fibrillation (and even reciprocating tachycardia) but never ventricular fibrillation. There were no significant differences between the two groups with respect to the following clinical parameters: sex, duration of symptoms, the type of tachycardia previously recorded, history of syncope and presence of underlying cardiac disease. With respect to the electrophysiological data, there were no differences in the point of anterograde block, the effective anterograde refractory period of the accessory pathway, the effective and functional refractory periods of the right atrium and atrial vulnerability. On the other hand, a significant difference was observed in the age of patients with ventricular fibrillation (29 +/- 13 years vs 36 +/- 12 years; p < 0.02), the prevalence of multiple accessory pathways (25% vs 7%; p < 0.04) with a dominant localisation in the postero-septal region (75% vs 47%, p < 0.026), preexcitation during exercise stress testing and under antiarrhythmic therapy (95% vs 68%, p < 0.037). The most discriminating parameter was the shorter RR interval during atrial fibrillation (172 +/- 23 ms vs 230 +/- 50 ms, p < 0.008). Multivariate analysis only showed one independent predictive factor: the minimum preexcited RR interval.(ABSTRACT TRUNCATED AT 250 WORDS)
BACKGROUND: Conversion of chronic atrial fibrillation (AF) is associated with atrial stunning, but the short-term effect of a brief episode of AF on left atrial appendage (LAA) emptying velocity is unknown. The purpose of this study was to determine whether a short episode of AF affects left atrial function and whether verapamil modifies this effect. METHODS AND RESULTS: The subjects of this study were 19 patients without structural heart disease undergoing an electrophysiology procedure. In 13 patients, LAA emptying velocity was measured by transesophageal echocardiography in the setting of pharmacological autonomic blockade before, during, and after a short episode of AF. During sinus rhythm, the baseline LAA emptying velocity was measured 5 times and averaged. AF was then induced by rapid right atrial pacing. After either spontaneous or electrical conversion, LAA emptying velocity was measured immediately on resumption of sinus rhythm and every minute thereafter. The mean duration of AF was 15.3+/-3.8 minutes. The mean baseline emptying velocity was 70+/-20 cm/s. The first post-AF emptying velocity was 63+/-20 cm/s (P=0.02 versus baseline emptying velocity). The post-AF emptying velocity returned to the baseline emptying velocity value after 3.0 minutes. The mean percent reduction in post-AF emptying velocity was 9.7+/-21% (range, 15% increase to 56% decrease). A second group of 6 patients were pretreated with verapamil (0.1-mg/kg IV bolus followed by an infusion of 0.005 mg. kg-1. min-1). In these patients, the first post-AF emptying velocity, 58+/-14 cm/s, was not significantly different from the pre-AF emptying velocity, 60+/-13 cm/s (P=0.08). CONCLUSIONS: In humans, several minutes of AF may be sufficient to induce atrial contractile dysfunction after cardioversion. When atrial contractile dysfunction occurs, there is recovery of AF within several minutes. AF-induced contractile dysfunction is attenuated by verapamil and may be at least partially mediated by cellular calcium overload.
Diagnostic right atrial stimulation was performed before and after atropine (1 mg i. v.) in 28 patients with or without ECG evidence of sinoatrial disease. Sinus-node recovery time was measured after rapid pacing had been stopped. Sinoatrial conduction time was calculated by premature atrial stimulation technique. Results are given for a control group of ten subjects with normal sinus-node function and 18 patients with sinoatrial disease. Using reaction of the pacemaker to single or multiple ectopic beats, it was found that sinus-node recovery time is determined not only by impulse generation but also sinoatrial conduction properties. The results indicate that, in a given patient, sinoatrial disease may be due to impairment of automaticity or sinoatrial conduction or a combination of both. Both stimulation procedures are of diagnostic value in patients who may require a pacemaker implantation.
BACKGROUND: Epoprostenol (prostaglandin I(2)) has become recognized as a therapeutic breakthrough that can improve hemodynamics and survival in patients with primary pulmonary hypertension (PPH). However, a significant number of patients have PPH that is refractory to epoprostenol, and lung transplantation has been the only remaining treatment option. METHODS AND RESULTS: The study subjects included 20 consecutive patients with PPH (mean pulmonary arterial pressure: 65+/-15 mmHg) who had received epoprostenol for more than 12 months. The patients were divided into 2 groups; responders and non-responders. In the non-responders, New York Heart Association (NYHA) functional class did not improve and mean right atrial pressure (mRA) increased to 8 mmHg or more, and additional sildenafil, a phosphodiesterase-5 inhibitor, was started. Six patients were included in the non-responders, whose mRA was 9+/-5 mmHg before and significantly increased to 13+/-3 mmHg after epoprostenol administration (p < 0.05). One patient died and the other 5 patients received oral sildenafil. The mRA of 12+/-4 mmHg (value before sildenafil) improved to 8+/-5 mmHg after sildenafil administration. Three patients were classified in the NYHA functional class 4 and improved to class 3, and 2 patients were in class 3 and remained in the same class after the addition of sildenafil. CONCLUSIONS: In patients with severe PPH refractory to epoprostenol treatment, additional oral sildenafil can improve pulmonary hemodynamics and symptoms. The combination therapy of epoprostenol and sildenafil is a new medical treatment to attempt before progressing to lung transplantation for patients with PPH refractory to epoprostenol.
Using subcostal echocardiography, 97 patients with diseases involving the right side of the heart and 15 normal subjects were examined in order to study the inferior vena cava (IVC) wall motion. All cases had a diagnostic cardiac catheterization and routine echocardiogram. The jugular pulse (JP) was recorded in 35 random cases contemporary to the IVC and tricuspid valve (TV) tracings. The aim of the study was to evaluate the variations of the IVC diameters in different cardiopathies and in relation to the right atrial mean pressure and the time-relationship of the IVC wall motion related to the cardiac rhythm and cycle, respiratory events, and JP and TV waves. The a, b, v, and y waves were identified on the IVC tracings and related to the respective waves of the JP and the points of closure and opening of the TV. The IVC a and v waves were coincident with the TV closure and opening, and therefore, considered as moments of maximal presystolic and systolic filling of the IVC. The JP a wave inscribed before, whereas the v wave did so after the same IVC waves, respectively. The IVC a wave was due to the atrial contraction and influenced by the cardiac rhythm. The emptying index (EI) was calculated from the diameters in a and b as a - b/a X %, whereas the collapsability index (CI) was calculated from the expiratory and inspiratory diameters as Ex - In/Ex X %, obtaining a good correlation with the right atrial mean pressure. Finally, the percentage systolic pulsation (SP) was calculated from the diameters in b and v as b - v/b X %. The indices of function of the IVC have been very useful in the evaluation of patients with raised heart pressure, tricuspid regurgitation, and pericardial effusion. From the present investigation it results that the IVC wall motion, more so than the JP waves, is an expression of right atrial and ventricular events, and that the above indices are an expression of the atrial and ventricular function in relation to the hemodynamic situation.
The coronary sinus of a healthy 18-year-old man who died of a skull fracture was found to communicate with both the right and left atria. The anomaly can function as an atrial septal defect; thus, it needs recognition in the treatment of a patient with an interatrial shunt with an apparently normal right atrium.
Potential benefits of heart transplantation are limited by the severe donor organ shortage. The AbioCor implantable replacement heart has been developed as a potential alternative to heart transplantation. We report our initial experience with the AbioCor in a bovine model. A right thoracotomy was performed for access to the heart and great vessels. After initiation of cardiopulmonary bypass, excision of the native ventricles was followed by orthotopic placement of the IRH and complete implantation of the transcutaneous energy transfer coil, controller, and battery pack. Invasive monitoring of IVC, SVC, carotid artery, pulmonary artery, and left atrial (LA) pressures was performed in all animals. Twelve calves have undergone implantation of the AbioCor. There were three early deaths, one from bleeding, one from respiratory failure, and one from neurodysfunction from low flow during CPB. Nine animals have had a normal recovery and survived a mean of 24.5 days (range, 4-48 days). All the animals have demonstrated excellent hemodynamics with the maintenance of normal pressures in the LA, SVC, IVC, pulmonary artery, and aorta. Adjustment of the right-sided internal hydraulic fluid shunt has allowed for control of right-left balance and, thereby, manipulation of left and right side filling pressures. Late morbidity has consisted of neck wound infection and sepsis, pneumonia, and bleeding. Successful orthotopic implantation of all components of the AbioCor has been achieved in a bovine model. This device has demonstrated restoration of normal hemodynamics and excellent function of the atrial hydraulic shunt to achieve right-left balance.
Clinical, angiographic, radiographic, and echocardiographic data on 46 neonates with Ebstein's anomaly presenting with cyanosis between 1954 and 1996 were reviewed to determine possible risk factors for mortality. Most patients (67%) presented at birth with 3 cases diagnosed in utero. Mean systemic oxygen saturation was 62+/-12%. An atrial septal defect > or = 4 mm was noted in 20 patients (44%). The patent right ventricle to pulmonary artery connection was present in 10 (22%), and pulmonary atresia was functional in 25 (54%) and anatomic in 11 patients (24%). Fifteen patients (35%) underwent surgical interventions. Total mortality was 70% (vs 14% in acyanotic patients diagnosed during the same time period; p <0.0001) and was related to low cardiac output and hypoxia in 20 patients (62%), postoperative complications in 8 (25%), and sudden death in 4 (13%). Kaplan-Meier survival estimates were 61% at age 1 week (95% confidence interval [CI], 47% to 75%), 48% at age 1 month (95% CI, 34% to 62%), and 36% at both 1 and 5 years of age (95% CI, 22% to 50%). Mortality improved from 81% in 1954 to 1985 to 47% in 1986 to 1996 (p = 0.04). Significant independent predictors of mortality included an atrial septal defect > or = 4 mm (odds ratio [OR] 2.39; p = 0.04), reduced left ventricular function (OR 4.10; p = 0.002), and functional or anatomic pulmonary atresia (OR 2.44, p = 0.003; and OR 5.97, p = 0.004, respectively). An echocardiographic ratio of the combined right atrial and atrialized right ventricular area to the area of the functional right ventricle and left heart >1.0 was 100% predictive of mortality.
This study was performed to examine cognitive function in patients with end-stage heart failure, to identify possible cardiovascular factors associated with cognitive function, and to evaluate changes in cognitive function in a subgroup of patients who received heart transplantation. An extensive battery of neuropsychological tests were given to 62 patients with end-stage cardiac failure as part of their evaluation for cardiac transplantation. Most patients were consecutive referrals, not selected because of cognitive complaints. A small subgroup of transplanted (n = 7) and non-transplanted (n = 4) patients received a repeat neuropsychological examination. At initial examination, approximately 50% of the patients met criteria for impairment in reference to normal control values. Higher stroke volume index and cardiac index and lower right atrial pressure were correlated with better cognitive function. In the subgroup of patients re-examined, the transplanted patients demonstrated significantly improved cognitive function, whereas the non-transplanted subjects were unchanged. These data indicate that in patients with end-stage heart failure there is a high prevalence of impaired cognitive function which is related to measures of cardiovascular efficiency. Preliminary evidence suggests that these impairments may be partially ameliorated by cardiac transplantation.
OBJECTIVE: To evaluate the acute effects of atrial pacing at different pacing sites on mechanical stunning after cardioversion of atrial fibrillation (AF). SETTING: Tertiary referral centre. PATIENTS: 20 patients with persistent AF were studied. INTERVENTIONS: Spontaneous echo contrast (SEC), left atrial appendage emptying velocity (LAAEV), and left atrial appendage emptying fraction (LAAEF) were assessed by transoesophageal echocardiography (TOE) during AF, after conversion to sinus rhythm, and during atrial pacing from the right atrial appendage, left lateral atrium, and both atria simultaneously. Transmitral inflow velocity of the atrial wave (TMIF-A) by TOE and the maximum P wave duration in 12 lead ECG were also measured during sinus rhythm and atrial pacing. MAIN OUTCOME MEASURES: Comparison of atrial mechanical function and P wave duration in 12 lead ECG during atrial pacing from different sites after cardioversion of AF. RESULTS: Compared with sinus rhythm, atrial pacing at 80 beats/min increased LAAEV from mean (SD) 14.6 (10.1) to 33.4 (19.8) cm/s (p = 0.001), LAAEF from 13.8 (8.5) to 32.1 (11.2)% (p < 0.001), and TMIF-A from 24.6 (11.9) to 45.6 (21.0) cm/s (p < 0.001) and reduced SEC grade from 2.6 (1.0) to 1.6 (0.9) (p < 0.001). These effects had a positive force-frequency relation. Biatrial pacing produced the shortest P wave duration and resulted in the most significant improvement in atrial function (LAAEV, 33.2 (19.3) v 53.7 (23.9) cm/s, p = 0.0001; LAAEF, 31.9 (11.1) v 46.2 (12.6)%, p < 0.0001; TMIF-A, 37.7 (18.3) v 54.1 (21.2) cm/s, p < 0.001; SEC grade, 1.4 (1.1) v 0.8 (0.9), p = 0.001, right atrial appendage versus biatrial pacing). CONCLUSIONS: Atrial pacing at increased rates can improve atrial mechanical function after cardioversion of persistent AF. Biatrial pacing may be the most effective technique to reverse atrial mechanical stunning.
Graft right ventricular failure after heart transplantation, secondary to preoperative functional pulmonary hypertension, was successfully managed in a 49-year-old patient using an extracorporeal right to left atrial bypass. We comment on the case and discuss the type of mechanical assistance used.
Pulmonary arterial end-diastolic and mean right atrial pressures were compared in 25 patients with acute myocardial infarction and in one patient with unstable angina. No consistent relationship was observed between these pressures. Simultaneous ventricular function curves relating the stroke work of each ventricle to its respective filling pressure were constructed on 34 occasions, dextran infusion or diuresis being used to alter the filling pressure. The curves from each ventricle were described mathematically by a quadratic (parabolic) function as well as by a straight line function and then compared by canonical correlation analysis. Alterations in the left ventricular function curves occurred with and without depression or right ventricular function curves. These hemodynamic measurements demonstrate that acute myocardial infarction can alter the relationship between left and right ventricular function.