Relation of systemic ventricular function quantified by myocardial performance index (Tei) to cardiopulmonary exercise capacity in adults after Mustard procedure for transposition of the great arteries

Prognostic significance of subpulmonary left ventricular size and function in patients with a systemic right ventricle

AIMS

To assess the additional prognostic significance of echocardiographic parameters of subpulmonary left ventricular (LV) size and function in patients with a systemic right ventricle (SRV).

METHODS AND RESULTS

All adults with an SRV who underwent transthoracic echocardiography in 2010-18 at a large tertiary centre were identified. Biventricular size and function were assessed at the most recent examination. The study endpoint was all-cause mortality or heart/heart-lung transplantation. We included 180 patients, with 100 (55.6%) males, with a mean age of 42.4 ± 12.3 years, of whom 103 (57.2%) had undergone Mustard/Senning operations and 77 (42.8%) had congenitally corrected transposition of great arteries. Over 4.9 (3.8-5.7) years, 28 (15.6%) patients died and 4 (2.2%) underwent heart or heart-lung transplantation. Univariable predictors of the study endpoint included age, New York Heart Association functional Class III or IV, history of atrial arrhythmias, presence of a pacemaker or cardioverter defibrillator, high B-type natriuretic peptide, and echocardiographic markers of SRV and subpulmonary LV size and function. On multivariable Cox analysis of echocardiographic variables, indexed LV end-systolic diameter [ESDi; hazard ratio (HR) 2.77 (95% confidence interval, CI) 1.35-5.68, P = 0.01], LV fractional area change [FAC; HR 0.7 (95% CI 0.57-0.85), P = 0.002), SRV basal diameter [HR 1.66 (95% CI 1.21-2.29), P = 0.005], and SRV FAC [HR 0.65 (95% CI 0.49-0.87), P = 0.008] remained predictive of mortality or transplantation. On receiver-operating characteristic analysis, subpulmonary LV parameters performed better than SRV markers in predicting adverse events.

CONCLUSION

SRV basal diameter, SRV FAC, LV ESDi, and LV FAC are significantly and independently associated with mortality and transplantation in adults with an SRV. Accurate echocardiographic assessment of both SRV and subpulmonary LV is, therefore, essential to inform risk stratification and management.

Contraction patterns of the systemic right ventricle: a three-dimensional echocardiography study

AIMS

To investigate contraction patterns of the systemic right ventricle (SRV) in patients with transposition of great arteries (TGA) post-atrial switch operation and with congenitally corrected transposition of great arteries (ccTGA).

METHODS AND RESULTS

Right ventricular (RV) volumes and ejection fraction (EF) were measured by three-dimensional echocardiography in 38 patients with the SRV (24 TGA and 14 ccTGA; mean age 45 ± 12 years, 63% male), and in 38 healthy volunteers. The RV contraction was decomposed along the longitudinal, radial, and anteroposterior directions providing longitudinal, radial, and anteroposterior EF (LEF, REF, and AEF, respectively) and their contributions to total right ventricular ejection fraction (LEFi, REFi, and AEFi, respectvely). SRV was significantly larger with lower systolic function compared with healthy controls. SRV EF and four-chamber longitudinal strain strongly correlated with B-type natriuretic peptide (BNP) level (Rho -0.73, P < 0.0001 and 0.70, P < 0.0001, respectively). In patients with TGA, anteroposterior component was significantly higher than longitudinal and radial components (AEF 17 ± 4.5% vs. REF 13 ± 4.9% vs. LEF 10 ± 3.3%, P < 0.0001; AEFi 0.48 ± 0.09 vs. REFi 0.38 ± 0.1 vs. LEFi 0.29 ± 0.08, P < 0.0001). In patients with ccTGA, there was no significant difference between three SRV components. AEFi was significantly higher in TGA subgroup compared with ccTGA (0.48 ± 0.09 vs. 0.36 ± 0.08, P = 0.0002).

CONCLUSION

Contraction patterns of the SRV are different in TGA and ccTGA. Anteroposterior component is dominant in TGA providing compensation for impaired longitudinal and radial components, while in ccTGA all components contribute equally to the total EF. SRV EF and longitudinal strain demonstrate strong correlation with BNP level and should be a part of routine echocardiographic assessment of the SRV.

Systolic dysfunction of the subpulmonary left ventricle is associated with the severity of heart failure in patients with a systemic right ventricle

BACKGROUND

The study aimed to assess the relation between echocardiographic parameters of subpulmonary left ventricular (LV) size and function, and the severity of heart failure in patients with a systemic right ventricle (SRV).

METHODS AND RESULTS

A total of 157 patients (89 post Mustard/Senning operations, 68 with congenitally corrected transposition of great arteries [ccTGA]) were included. The size and function of the SRV and subpulmonary LV were assessed on the most recent echocardiographic exam. Clinical data were collected from the electronic records. The majority (133, 84.7%) were in NYHA functional class 1-2. Median BNP concentration was 79.5[38.3-173.3] ng/l, and 100 (63.7%) patients were receiving heart failure therapy. Both LV and SRV fractional area change (FAC) differed significantly between patients with NYHA class 1-2 vs 3-4 (48[41.5-52.8]% vs 34[28.6-38.6]%, p < 0.0001 and 29.5[23-35]% vs 22[20-27]%, p < 0.0001, respectively), but LV FAC had a higher discriminative power for functional class >2 than SRV FAC (AUC 0.90, p < 0.0001 vs 0.79; p < 0.0001, respectively). A LV FAC cut-off value <39.2% had the highest accuracy in identifying patients with NYHA class 3-4 (sensitivity 83% and specificity 88%). In multivariable logistic regression analysis, LV FAC and SRV FAC independently associated to NYHA class 3-4 (OR 0.80 [95%CI 0.72-0.88], p < 0.0001 and OR 0.85 [95%CI 0.76-0.96], p = 0.007, respectively).

CONCLUSIONS

Subpulmonary LV systolic dysfunction is associated with NYHA functional class 3-4 in patients with ccTGA or after Mustard or Senning operation. Careful evaluation of the subpulmonary LV should be a part of the routine assessment of patients with a SRV.

Global longitudinal strain correlates to systemic right ventricular function

Abstract

Background

The aim of this retrospective study was to evaluate the relationship between right ventricular function derived from cardiac magnetic resonance imaging (CMR), echocardiography and exercise stress test performance, NT-proBNP (N-terminal proB-type natriuretic peptide) level and NYHA class in patients with a systemic right ventricle.

Methods

All patients with congenitally corrected transposition of the great arteries (ccTGA), or transposition of the great arteries after Mustard or Senning procedures, (TGA) followed at our centre who had undergone CMR, echocardiography, an exercise stress test and blood sampling, were included in the study.

Results

We examined 11 patients (six after the Senning procedure, one after the Mustard procedure, and four ccTGA) who have a median age of 32 years (22-67 years). A significant correlation was observed between the systemic ventricular function, expressed as the CMR-derived right ventricular ejection fraction and the right ventricular global longitudinal strain (r= -0.627; p=0.039).

Conclusion

We have demonstrated that in patients with ccTGA or TGA right ventricular global longitudinal strain may be useful in the evaluation of the systemic right ventricular function.

Heart rate response during exercise predicts exercise tolerance in adults with transposition of the great arteries and atrial switch operation

BACKGROUND

To assess the relationship between heart rate response and exercise tolerance in adults with systemic right ventricle (sRV) after atrial switch repair for Transposition of the Great Artery (TGA) in addition to other physiological parameters.

METHODS

All patients with a sRV after atrial switch repair for TGA followed in our institution between June 2015 and April 2018 who underwent cardiopulmonary exercise testing (CPET) were analyzed. Cardiac imaging performed within a six-month time period of the CPET were also collected. Chronotropic incompetence was defined as the inability to achieve 80% of age-predicted maximal heart rate reserve (HRR) and <62% on a beta-blocker regimen. Patient characteristics were assessed according to tertiles of the percentage of predicted pVO2 (%ppVO2).

RESULTS

We studied 70 patients (mean of age 32.4 ± 7.6 years old, 51 males). Mean peak oxygen uptake was 21.5 ± 5.8 mL/kg/min, corresponding to a %ppVO2 of 57 ± 14.1% while mean VE/VCO2 slope was 37.1 ± 8.2. There was a trend toward more exaggerated hyperventilation in patient with lower pVO2. Mean age-adjusted HRR was 68.5 ± 19%. Chronotropic incompetence was observed in 65.7% and was correlated with %ppVO2 (r = 0.482; p < 0.001) as physical training evaluated with Ventilatory Anaerobic threshold (r = 0.571; p < 0.001), while no difference was found based on respiratory parameters. No echocardiographic or Magnetic Resonance Imaging parameters assessing sRV systolic function at rest were correlated with %ppVO2.

CONCLUSIONS

Exercise limitation is related to the inability to increase cardiac output during exercise and is notably due to the degree of chronotropic incompetence.

Right ventricular systolic dysfunction at rest is not related to decreased exercise capacity in patients with a systemic right ventricle

BACKGROUND

To evaluate the relationship between right ventricular (RV) systolic dysfunction at rest and reduced exercise capacity in patients with a systemic RV (sRV).

METHODS

All patients with congenitally corrected transposition of the great arteries (ccTGA) or complete TGA after atrial switch (TGA-Mustard/Senning) followed in our institution between July 2011 and September 2017 who underwent cardiac imaging within a six-month time period of cardiopulmonary exercise testing (CPET) were analyzed. We assessed sRV systolic function with TAPSE and fractional area change on echocardiogram and, if possible, with ejection fraction, global longitudinal and circumferential strain on cardiac magnetic resonance (CMR) imaging.

RESULTS

We studied 105 patients with an sRV (median age 34 [IQR 28-42] years, 29% ccTGA and 71% TGA-Mustard/Senning) of which 39% had either a pacemaker (n = 17), Eisenmenger physiology (n = 6), severe systemic atrioventricular valve regurgitation (n = 14), or peak exercise arterial oxygen saturation < 92% (n = 17). Most patients were asymptomatic or mildly symptomatic (NYHA class I/II/III in 71/23/6%). Sixty-four percent had evidence of moderate or severe sRV dysfunction on cardiac imaging. Mean peak oxygen uptake (pVO2) was 24.1 ± 7.4 mL/kg/min, corresponding to a percentage of predicted pVO2 (%ppVO2) of 69 ± 17%. No parameter of sRV systolic function as evaluated on echocardiography (n = 105) or CMR (n = 46) was correlated with the %ppVO2, even after adjusting for associated cardiac defects or pacemakers.

CONCLUSIONS

In adults with an sRV, there is no relation between echocardiographic or CMR-derived sRV systolic function parameters at rest and peak oxygen uptake. Exercise imaging may be superior to evaluate whether sRV contractility limits exercise capacity.

BNP in children with congenital cardiac disease: is there now sufficient evidence for its routine use?

Interest in brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in the management of children with CHD has increased. There are, however, no current guidelines for their routine use. The aim of this review article is to provide an update on the data regarding the use of BNP/NT-proBNP in the evaluation and surgical treatment of children with CHD. BNP/NT-proBNP levels in children with CHD vary substantially according to age, laboratory assay methods, and the specific haemodynamics associated with the individual congenital heart lesion. The accuracy of BNP/NT-proBNP as supplemental markers in the integrated screening, diagnosis, management, and follow-up of CHD has been established. In particular, the use of BNP/NT-proBNP as a prognostic indicator in paediatric cardiac surgery has been widely demonstrated, as well as its role in the subsequent follow-up of surgical patients. Most of the data, however, are derived from single-centre retrospective studies using multivariable analysis; prospective, randomised clinical trials designed to evaluate the clinical utility and cost-effectiveness of routine BNP/NT-proBNP use in CHD are lacking. The results of well-designed, prospective clinical trials should assist in formulating guidelines and expert consensus recommendations for its use in patients with CHD. Finally, the use of new point-of-care testing methods that use less invasive sampling techniques - capillary blood specimens - may contribute to a more widespread use of the BNP assay, especially in neonates and infants, as well as contribute to the development of screening programmes for CHD using this biomarker.

Relationship between Exercise Parameters and Noninvasive Indices of Right Ventricular Function in Patients with Biventricular Circulation and Systemic Right Ventricle

OBJECTIVES

In patients with systemic right ventricles (RVs) in a biventricular circulation, exercise capacity and RV function often deteriorate over time and echocardiographic assessment of systemic RV function is difficult. The purpose of this study was to examine the relationship between exercise capacity and RV function and to determine which noninvasive imaging parameters correlate most closely with exercise capacity.

DESIGN

Patients with a systemic RV (D-loop transposition of the great arteries [TGA] after atrial switch procedure or physiologically "corrected" TGA) who underwent cardiopulmonary exercise testing (CPX) and noninvasive imaging (cardiac magnetic resonance [CMR] and echocardiography [echo]) within 1 year of CPX were identified. Regression analysis was used to evaluate the relationship between exercise variables and noninvasive indices of ventricular function.

RESULTS

We identified 92 patients with 149 encounters (mean age 31.0 years, 61% men, 70% D-loop TGA) meeting inclusion criteria. Statistically significant correlations between % predicted peak oxygen uptake (%pVO2 ) and RV ejection fraction (EF) (r = 0.29, P = .0007), indexed RV end-systolic volume (r = -0.25, P = .002), and Tei index (r = -0.22, P = .03) were found. In patients without additional hemodynamically significant lesions, the correlations between %pVO2 and RV EF (r = 0.37, P = .0007) and the Tei index (r = -0.28, P = .03) strengthened and a correlation emerged between %pVO2 and dP/dtic (r = 0.31, P = .007). On multivariable analysis, Tei index was the only statistically significant correlate of %pVO2 (P = .04).

CONCLUSIONS

In patients with systemic RVs in a biventricular circulation, CMR-derived RVEF and echo-derived Tei index correlate with %pVO2 . On multivariable analysis, the Tei index was the strongest predictor of peak %pVO2 response.

Right ventricular function with standard and speckle-tracking echocardiography and clinical events in adults with D-transposition of the great arteries post atrial switch

BACKGROUND

The prognostic value of deformation parameters of the systemic right ventricle in adults with D-transposition of the great arteries and prior atrial switch has not been reported.

METHODS

Sixty-four adults with D-transposition of the great arteries and prior atrial switch (mean age, 29 ± 6 years; 22 women; mean right ventricular [RV] fractional area change, 22.9 ± 7.5%; 31 with pacemakers at baseline) and no histories of heart failure or ventricular tachycardia were prospectively evaluated. Global longitudinal strain (GS), global systolic strain rate (GSRs), and global early diastolic strain rate (GSRe) of the right ventricle were measured using speckle tracking from apical views and compared with standard parameters of RV function (fractional area change, tricuspid annular plane systolic excursion, tissue Doppler velocities, and isovolumic acceleration) for association with and potential prediction of clinical events, defined as incident stage C heart failure or ventricular tachycardia.

RESULTS

Baseline RV GS, GSRs, and GSRe were -12.5 ± 3.0%, -0.59 ± 0.14 sec(-1), and 0.68 ± 0.22 sec(-1), respectively. After a median of 2.4 years (interquartile range, 1.5-4.1 years), 12 patients (19%) presented with clinical events (heart failure in 11 patients, ventricular tachycardia in one patient). In Cox models, RV GS had the strongest association with clinical events (hazard ratio [HR] per 1%, 1.35; 95% confidence interval [CI], 1.14-1.58; P < .001), followed by GSRs (HR per 0.01 sec(-1), 1.06; 95% CI, 1.02-1.11; P = .006), GSRe (HR per -0.01 sec(-1), 1.04; 95% CI, 1.00-1.07; P = .031), and fractional area change (HR per -1%, 1.08; 95% CI, 1.00-1.17; P = .047). Other measures of RV function were not significantly associated with risk for events. In receiver operating characteristic analysis, RV GS ≥ -10% optimally predicted future events (C = 0.83; 95% CI, 0.71-0.91; P < .001).

CONCLUSIONS

Reduced longitudinal GS of the systemic right ventricle is associated with increased risk for clinical events among patients with D-transposition of the great arteries and prior atrial switch.

Echocardiographic Assessment of Left Ventricular Diastolic Dysfunction: Differentiating a Pulmonary Vascular From a Pulmonary Venous Origin of Pulmonary Hypertension

Pulmonary hypertension (PH) is a heterogeneous condition that may be due to a primary pulmonary arteriolar vasculopathy (pulmonary arterial hypertension or PAH: Group I), or secondary to left heart disease and pulmonary venous hypertension (PVH: Group II), chronic respiratory conditions (Group III), chronic thromboembolic disease (CTEPH: Group IV) or miscellaneous/multifactorial causes (Group V).12 The clinical diagnoses themselves are as diverse as the varied hemodynamic compositions of PH. Pulmonary hypertension ultimately results from varying interactions between pulmonary blood flow, pulmonary vascular resistance (PVR), conduit vessel compliance, and downstream left atrial (LA) pressure. Therefore, PH may also result from abnormalities in one or more of these factors. Patients with PAH, CTEPH, and most Group III patients have a “precapillary” hemodynamic profile with a normal LA pressure and an increased PVR as the primary mechanism of their PH. In contrast, patients with PVH (“postcapillary”) have increased LA pressure, most often with a normal or only mildly elevated PVR.

Transposition of the great arteries

Many patients with ventriculoarterial discordance have survived to adulthood. Those with complete transposition of the great arteries have often had an atrial switch procedure (Mustard or Senning operation) performed, which leaves the morphological right ventricle supporting the systemic circulation. It has been also reported previously undiagnosed congenitally corrected transposition of the great arteries. We present the complete transposition of the great arteries in an 8-year-old Romanian child with a septal defect of the ventricle (functionally single ventricle).

Brain natriuretic peptide as a biomarker of systemic right ventricular function in patients with transposition of great arteries after atrial switch operation

BACKGROUND

Assessment of systemic right ventricular (RV) function is inherently difficult. In adults, plasma brain natriuretic peptide (BNP) level has been shown to reflect systemic ventricular dysfunction. We sought to test the hypothesis that plasma BNP is a biomarker of systemic RV function in patients after atrial switch operation.

METHODS

We determined the RV function in 44 patients, 35 after Senning and 9 after Mustard operation, aged 19.7+/-4.0 years, by tissue Doppler echocardiography and determination of myocardial performance index (MPI). The results were compared to the left ventricular function of 14 age-matched controls. Their plasma BNP levels were correlated with indices of systemic ventricular function.

RESULTS

Compared with controls, the patients had greater MPI (p<0.001), lower systemic ventricular free wall-annular early diastolic (p<0.001), late diastolic (p<0.001), and systolic velocities (p=0.001), lower septal-annular early diastolic (p<0.001), late diastolic (p<0.001), and systolic velocities (p<0.001), and higher BNP levels (p=0.03). Plasma BNP levels correlated positively with MPI (r=0.43, p=0.001) and negatively with the free wall- and septal-annular myocardial velocities (r=-0.32 to -0.47, p<0.05). The area under the receiver operating characteristic curve for BNP to detect ventricular dysfunction (MPI >0.45) in patients was 0.67 (p=0.04). A BNP level of 36 pg/ml had a sensitivity of 55%, specificity of 86%, positive predictive value 80%, negative predictive value of 64%, and an accuracy of 70% for detecting systemic ventricular dysfunction.

CONCLUSIONS

Plasma BNP has modest accuracy in the detection of systemic RV dysfunction in patients after atrial switch operation.

Elevated brain natriuretic peptide and reduced exercise capacity in adult patients operated on for tetralogy of fallot is due to biventricular dysfunction as determined by the myocardial performance index

Although tetralogy of Fallot (TOF) can be repaired surgically, residual lesions that cause abnormal ventricular load can eventually lead to heart failure. Subclinical biventricular dysfunction in these patients may be detected only by using suitably sensitive indexes. The Tei index determined by the pulsed Doppler method enables the measurement of left ventricular (LV) and right ventricular (RV) function. This study was designed to evaluate the biventricular Tei indexes in adults with operated congenital heart disease and to correlate these indexes with cardiopulmonary capacity and neurohormonal activation. Fifty-nine patients with surgically corrected TOF and 52 patients with operated left-to-right-shunt defects were included in the study. Patients with TOF showed significantly greater LV and RV Tei indexes than those with left-to-right-shunt defects (LV Tei index 0.50 +/- 0.09 vs 0.34 +/- 0.05, RV Tei index 0.37 +/- 0.1 vs 0.25 +/- 0.06; p <0.0001). Peak oxygen uptake was significantly reduced in the patients with TOF (25 +/- 6 vs 32 +/- 6 ml x kg(-1) x min(-1), p <0.0001) and was correlated inversely with the LV Tei index (r = -0.61, p <0.0001). N-terminal-pro-brain natriuretic peptide was significantly increased in patients with TOF (150 +/- 141 vs 57 +/- 39 pg/ml, p <0.0001). In conclusion, in asymptomatic or minimally symptomatic patients with TOF, biventricular dysfunction is detected by the Tei index. Further indexes for heart failure in these patients are increased circulating plasma N-terminal-pro-brain natriuretic peptide and impaired peak oxygen uptake. The combined determinations of these 3 variables enable the identification of congenital heart disease with impaired cardiac function before they become clinically symptomatic.