Uhl's Anomaly in Adulthood

Uhl's anomaly is a rare congenital syndrome characterized by the absence of right ventricular myocardium. The widely accepted pathological mechanism is intrauterine myocardial apoptosis. Uhl's syndrome carries a poor prognosis. In rare situations, patients with Uhl's anomaly reach adulthood. We will present a case of a 29-year-old patient with Uhl's syndrome treated at our center, highlighting the diagnostic, surgical, and postoperative challenges in management.

Valvulogenesis of a living, innervated pulmonary root induced by an acellular scaffold

Heart valve disease is a major cause of mortality and morbidity worldwide with no effective medical therapy and no ideal valve substitute emulating the extremely sophisticated functions of a living heart valve. These functions influence survival and quality of life. This has stimulated extensive attempts at tissue engineering "living" heart valves. These attempts utilised combinations of allogeneic/ autologous cells and biological scaffolds with practical, regulatory, and ethical issues. In situ regeneration depends on scaffolds that attract, house and instruct cells and promote connective tissue formation. We describe a surgical, tissue-engineered, anatomically precise, novel off-the-shelf, acellular, synthetic scaffold inducing a rapid process of morphogenesis involving relevant cell types, extracellular matrix, regulatory elements including nerves and humoral components. This process relies on specific material characteristics, design and "morphodynamism".

Assessment of superior cavo-pulmonary anastomoses (Glenn shunt) by cardiac magnetic resonance imaging in comparison with multi-slice computed tomography

Background

Multi-slice computed tomography (MSCT) angiography is the gold standard imaging modality to evaluate the patency of Glenn shunt and the presence of veno–veno collaterals. The goal of this study is to evaluate the ability of two cardiac magnetic resonance imaging (MRI) techniques to assess the patency of Glenn shunt and the presence of veno–veno collaterals compared to MSCT angiography.

Results

Patients with Glenn shunt had MSCT angiography and cardiac MRI using two techniques: TWIST (Time-resolved angiography With Stochastic Trajectories) and the three-dimensional (3D) post-contrast whole heart techniques. MSCT angiography and cardiac MRI images were post-processed for quantitative and qualitative assessment of Glenn shunt and veno–veno collaterals. Our study included 29 patients (17 male, 59%) with Glenn shunt, the median age was 22 years (range 3–36 years). 3D post-contrast whole heart images give similar results compared to MSCT angiography results in the evaluation of Glenn shunt and veno–veno collaterals, 100% agreement in Glenn shunt visualization and agreement was 86.2% in the detection of veno–veno collaterals with a perfect agreement (kappa = 1) as regards their proximal connection to superior vena cava (SVC). While TWIST showed lower agreement compared to MSCT angiography results, 87.5% agreement in Glenn shunt visualization and agreement was 68.9% in the detection of veno–veno collaterals with poor agreement (kappa = 0.266) as regards their proximal connection to SVC.

Conclusions

3D post-contrast whole heart MRI images have similar results as MSCT angiography in the evaluation of superior cavo-pulmonary anastomosis and can be a good and safer alternative to MSCT angiography.

Novel concepts and early results of repairing common arterial trunk

OBJECTIVES

Common Arterial Trunk (CAT) continues to have a very poor prognosis globally. To address that, we have developed a novel technique targeting key concepts for the correction of all components of the anomaly, using autologous arterial tissue. This aims to enhance results, availability worldwide, and importantly to avoid the need for repeated reoperations.

METHODS

From January 2019 to 4 January 2021, all patients with isolated CAT had repair of the defect using autologous arterial trunk tissue with direct right ventricle (RV) to pulmonary artery (PA) connection. Clinical outcomes, follow-up which included multi-slice computed tomography 3D segmentation and 4D cardiovascular magnetic resonance flow, are presented.

RESULTS

Twenty patients were included in the study (median age 4.5 months). There were 2 hospital deaths due to systemic infection and pulmonary hypertensive crisis, respectively. Following discharge all patients remained asymptomatic with no signs of heart failure and improved pattern of growth (median follow-up: 8 months). Early postoperative 3D segmentation showed a conical shaped neo-right ventricular outflow chamber connecting the body of the RV to the main PA through a valveless ostium, and normal crossing of PA and neo-aorta. 4D cardiovascular magnetic resonance pattern of flow showed normal rapid laminar flow through the atrioventricular valves followed by a vortex towards the outflow tracts. There was laminar flow through the neo-aorta and neo-PA with velocity not exceeding 2.5 m/s. The PA regurgitant fraction was 25 ± 5% and was limited to early diastole.

CONCLUSIONS

The initial results of utilizing the key concepts, using autologous arterial tissue for the repair of CAT, are encouraging, both clinically and by multimodality imaging.

A quantitative assessment of aorta root rotation in patients with tetralogy of Fallot evaluated by MSCT

Lack of conal rotation and conal malseptation is a characteristic anatomical feature for TOF which lead to dextroposed position of aorta and significant RVOT narrowing. The quantitative assessment of these anatomical features using modern cardiac imaging modality has been rarely discussed in the literature. All TOF scanned had in our center from 2013 till 2019 were included. The angle of aortic root rotation was recorded by measuring the angle between a line connecting the midpoint of the non-coronary sinus to the anterior commissure and another line along the interatrial septum. Rotation angles were correlated with proximal main pulmonary artery (MPA) size indexed to BSA. 287 TOF patients were included, 258 patients (91%) had TOF with pulmonary stenosis (TOF-PS) including 138 male (54%), median age 2 years (2 months-40 years), and 29 patients (9%) had TOF with pulmonary atresia (TOF-PA) including 17 male (59%), median age 5 years (1 m-33 years). The whole cases demonstrated clockwise rotation of the aortic root. The mean rotation angle in TOF-PS group was 52.6 ± 20.9° and in TOF-PA group was 64.9 ± 13.9°. Proximal MPA diameter was 11.1 ± 5.9 mm/m2. There was a significant negative correlation between aortic root rotation angle and proximal MPA diameter (r = - 0.262, P = 0.000). The rotation angle of aortic root was significantly higher in TOF-PA compared to TOF-PS (64.9 ± 13.9° vs. 52.6 ± 20.9°, P = 0.001, respectively). MSCT provide a quantitative measurement methodology of conal malseptation and its effect in TOF patients. There is a clockwise rotation angle of the aortic root in TOF patients that correlates negatively with proximal MPA size. TOF-PA have a larger rotation angle of aortic root.

Left Ventricular Remodeling Following Balloon Mitral Valvuloplasty in Rheumatic Mitral Stenosis: Magnetic Resonance Imaging Study

Background: Rheumatic heart disease affects primarily cardiac valves, it could involve the myocardium either primarily or secondary to heart valve affection. The influence of balloon mitral valvuloplasty (BMV) on left ventricular function has not been sufficiently studied.

Aim: To determine the influence of balloon mitral valvuloplasty (BMV) on both global and regional left ventricular (LV) function.

Methods: Thirty patients with isolated rheumatic mitral stenosis (MS) were studied. All patients had cardiac magnetic resonance imaging (CMR) before, 6 months and 1 year after successful BMV. LV volumes, ejection fraction (EF), regional and global LV deformation, and LV late gadolinium enhancement were evaluated.

Results: At baseline, patients had median EF of 57 (range: 45–69) %, LVEDVI of 74 (44–111) ml/m² and LVESVI of 31 (14–57) ml/m² with absence of late gadolinium enhancement in all myocardial segments. Six months following BMV, there was a significant increase in LV peak systolic global longitudinal strain (GLS) (−16.4 vs. −13.8, p < 0.001) and global circumferential strain (GCS) (−17.8 vs. −15.6, p = 0.002). At 1 year, there was a trend towards decrease in LVESVI (29 ml/m², p = 0.079) with a significant increase in LV EF (62%, p < 0.001). A further significant increase, compared to 6 months follow up studies, was noticed in GLS (−17.9 vs. −16.4, p = 0.008) and GCS (−19.4 vs. −17.8 p = 0.03).

Conclusions: Successful BMV is associated with improvement in global and regional LV systolic strain which continues for up to 1 year after the procedure.

Multiparametric Rest and Dobutamine Stress Magnetic Resonance in Assessment of Myocardial Viability

BACKGROUND

MR feature-tracking (FT) is a novel technique that quantitatively calculates myocardial strain and can assess myocardial viability.

PURPOSE

To evaluate the feasibility of FT at rest and with low-dose dobutamine (LDD), visual assessment of contractility with LDD and left ventricle (LV) end-diastolic wall thickness (EDWT) in the assessment of viability in ischemic cardiomyopathy (ICM) patients compared to delayed gadolinium enhancement (DGE).

STUDY TYPE

Prospective.

SUBJECTS

Thirty ICM patients and 30 healthy volunteers.

FIELD STRENGTH/SEQUENCES

A 1.5 T with balanced steady-state free precession (bSSFP) cine and phase-sensitive inversion prepared segmented gradient echo sequences.

ASSESSMENT

LDD (5 μg/kg/min and 10 μg/kg/min) was administered in the patient group. LV was divided into 16 segments and MR-FT was derived from bSSFP cine images using dedicated software. Viable segments were defined as those with a dobutamine-induced increase in resting MR-FT values >20%, a dobutamine-induced increase in systolic wall thickening ≥2 mm by visual assessment, ≤50% fibrosis on DGE, and resting EDWT ≥5.5 mm.

STATISTICAL TESTS

One-way analysis of variance (ANOVA), two-sampled t-test, paired samples t-test, and receiver operating characteristic (ROC) curve analysis. A P value < 0.05 was considered statistically significant.

RESULTS

Resting peak global circumferential (Ecc) and radial (Err) strains were significantly impaired in patients compared to controls (-11.7 ± 7.9 vs. -20.1 ± 5.7 and 19.7 ± 13.9 vs. 32.7 ± 15.4, respectively). Segments with no DGE (n = 354) and ≤ 50% (n = 38) DGE showed significant improvement of both Ecc and Err with LDD while segments with >50% DGE (n = 88) showed no improvement. In comparison to viable and nonviable segments identified by reference-standard DGE, the sensitivity, specificity, and diagnostic accuracy of the four methods were: 74%, 92%, and 89%, respectively, for Ecc; 70%, 89%, and 86%, respectively, for Err; 67%, 88%, and 84% for visual assessment; and 39%, 90%, and 80% for EDWT.

DATA CONCLUSION

Quantitative assessment of MR-FT, along with EDWT and qualitative visual assessment of myocardial contractility with LDD, are feasible alternative methods for the assessment of myocardial viability with moderate sensitivity and high specificity.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: Stage: 2.

Coronary artery anomalies in tetralogy of Fallot patients evaluated by multi slice computed tomography; myocardial bridge is not a rare finding

Based on coronary angiography and interoperative inspection, anomalous origin of coronary artery crossing the right ventricular outflow tract (RVOT) is common in tetralogy of Fallot (TOF) patients. However, other coronary anomalies may be underestimated due to the overlying myocardium, epicardial fat, or adhesions due to previous palliative surgery. Currently, coronary artery visibility dramatically improved by multislice computed tomography (MSCT). We performed this study to assess the coronary arteries anatomy in TOF patients using MSCT.All TOF patients underwent MSCT examination at our centre from 2013 till 2019 were included. Assessment of the coronary arteries' origin and course were performed. Presence of myocardial bridge were assessed, and indexed RV mass was calculated.318 TOF patients were included, median age 2 years (range 1 month-46 years), 175 males (55%). The abnormal coronary artery origin and course were detected in 20 patients (6%); coronary artery crossed RVOT in 13 patients (65%), 5 patients (25%) had a retro-aortic course and 2 patient (10%) had inter-arterial course. Myocardial bridges of left anterior descending artery or/and right coronary artery were reported in 100 patients (36%), no myocardial bridge of left circumflex was reported. RV mass was 29.0 ± 21.1 g/m2. There was no correlation between RV mass and presence of myocardial bridges.MSCT is a useful imaging modality for detection of coronary arteries anomalies in TOF patients. Coronary artery crossing RVOT is not the only abnormal course and myocardial bridging is not a rare finding. Further studies are needed to demonstrate the clinical significance of these observations.

Pulmonary artery banding in a modified Mustard operation improves biventricular geometry and function

Patients with transposition of great arteries, with intact interventricular septum (TGA-IVS) and deconditioned left ventricle, represent a considerable challenge in developing countries. The modified Mustard operation was shown to provide a significant improvement for these patients, particularly by enhancing atrial functions and left ventricular filling. Yet, the problems of the systemic right ventricular dysfunction and the resulting secondary tricuspid regurgitation (TR) remain to be of major concern. In addition, the deviation of the interventricular septum towards the left side markedly impairs ventriculo-ventricular interaction and predisposes to dynamic left ventricular outflow tract obstruction (LVOTO). We report that adding a moderately loose pulmonary artery banding to the modified Mustard operation in a case of TGA-IVS results in improvement of biventricular geometry and function, tricuspid and mitral valve functions and disappearance of dynamic LVOTO.

A New Technique for Shaping the Aortic Sinuses and Conserving Dynamism in the Remodeling Operation

BACKGROUND

Preserving dynamism and recreating the sinuses in the Dacron graft are thought to be important for optimizing results of aortic valve-conserving operations.

METHODS

We describe a novel technique that preserves dynamism and recreates the sinotubular junction. In addition, it tailors 3 sinuses of defined longitudinal and transverse curvatures in a straight Dacron tube during the operation. The technique has been used in 6 patients with varied aortic root pathology. We performed preoperative and postoperative multimodality imaging using computerized image analysis as well as 3-dimensional models.

RESULTS

There was no early or midterm death. Upon discharge, patients were clinically well, with echocardiographic evidence of minimal (3 patients) or mild (3 patients) aortic regurgitation. Computed tomography and cardiac magnetic resonance imaging with extensive image analysis of the aortic root size, shape, and function showed partial or complete normalization of these parameters. This included the shape and dynamism of the aortic annulus and the size and shape of the geometric (effective) orifice. The 4-dimensional magnetic resonance imaging pattern of flow in the sinuses and ascending aorta showed favorable vortices in the sinuses, right-handed helical flow, and marked diminution of energy loss in the ascending aorta.

CONCLUSIONS

The novel technique described here is simple, practical, and cost-effective because it uses a widely available straight Dacron tube. The technique does not use rigid internal or external support. The early results are encouraging. Larger series with longer follow-up are required.

Impact of balloon mitral valvuloplasty on left ventricular rotational deformation: Magnetic Resonance Imaging follow up study

In patients with rheumatic mitral stenosis (MS), some previous studies have investigated the influence of balloon mitral valvuloplasty (BMV) on left ventricular (LV) systolic function. However, the impact of BMV on LV twisting motion in this clinical setting has not been studied before yet. To describe changes in LV torsion in patients with rheumatic MS following BMV. Thirty patients (median age 33 years, 22 women) with isolated severe MS were studied. CMR myocardial tissue tagging was used for assessment of LV rotational deformation. LV torsion was calculated as the twist value (the net difference between apical counterclockwise and basal clockwise rotation) normalized to the length of the ventricle and multiplied by the mean radius at the base and apex. All patients had CMR studies before, 6 months and 1 year after successful BMV. At baseline, patients had a mitral valve area of 0.9 (0.6-1.3) cm², mean pressure gradient of 12.5 (8-24) mmHg across the valve as measured by transthoracic echocardiography. Median LV ejection fraction (LVEF) estimated by CMR was 57 (range: 45-69) %. A significant improvement in LV base-apex torsion was shown at 6 months (3.3° vs. 2.5°, p < 0.001) with a further improvement at 1 year (4.1° vs. 3.3°, p = 0.05). Similar pattern of change was seen in LV base-mid torsion with a significant increase at 6 months (3.6° vs. 2.3°, p < 0.001) and a further increase at 1 year (4.7° vs. 3.6°, p = 0.007). These changes were associated with a significant increase in LVEF (62% vs. 57%, p < 0.001) at 1 year following BMV. Successful BMV is associated with a significant improvement in LV torsion that is accompanied by a significant improvement in LVEF.

Right ventricular crypts in a myocardial bridge: Relevance to surgical relief

Crypts are very thin walled invaginations from the cavity of the left ventricle into the compact myocardium. With the advent and increased application of multimodality imaging, crypts are being increasingly identified in both normal individuals and patients, with various conditions including HCM, before and after the development of LV hypertrophy, LV non-compaction and hypertensive heart disease. to date crypts have not been described in the right ventricle. We here describe for the first time, RV crypts which were extending into a myocardial bridge, in a patient with HCM and dynamic obstruction of the LAD coronary artery. We also document and discuss the serious complications which can arise from crypts, and highlight the importance of preoperative identification of crypts. Further studies are required to determine the fetal origin of crypts and their clinical significance

P5272Right versus Left Ventricular Remodelling after Surgical myectomy for HOCM

Background

Surgical myectomy for (HOCM) results in complex structural and functional changes. “Remodelling” in different cardiac chambers. To date, changes in the Right versus the left Ventricle have not been studied.

Methods

Fourty five patients (mean age = 32±16, 68% males) who underwent extended septal myectomy for LVOTO and Fourty “normal” controls (mean age = 32±12 years, 52% males) were studied by cardiac magnetic resonance imaging (CMR). The patients were studied pre-operatively and 6–18 months post-operatively (median = 9 months). The images were analysed by both commercial and in-house software.

Results

After myectomy. Follow up CMR showed changes in RV mass (21±5 to 23±7) g/m2, volume (60±15 to 66±12) ml/m2 and shape using 3 different methods. RV deformation parameters showed significant changes with circumferential strain (−8±2 to −14±4), filling (38±16 to 62±19) ml/s/m2 and ejection rate (−44±17 to −75±22). Changes in RV were substantially higher than those observed in the LV (Figure. 1, Table. 1). All patients reported significant symptomatic improvement with 31 (78%) patients in NYHA class I and 9 (22%) in class II at follow up. Significant reduction in peak gradient across the LVOT by 75%.

Table 1. Summary of reported parameters related to RV Shape for pre and post operation HOCM patients and Normal Healthy Volunteers LV RV Pre Post Normal P-value Pre Post Normal P-value EDV ml/m2 75±18 81±14 73±10 0.005 60±15 66±12 71±12 0.002 ESV ml/m2 20±9 24±8 26±6 0.008 16±7 19±9 26±7 0.02 SV ml/m2 56±13 57±10 51±13 0.38 44±11 48±10 49±14 0.009 EF 74±7 70±7 65±5 0.001 74±8 72±7 64±6 0.228 Mass g/m2 74±33 62±29 27±8 0.0456 21±5 23±7 18±5 0.2100 PFR ml/m2 173±48 141±48 141±40 <0.0001 38±16 62±19 55±24 <0.0001 PER ml/m2 −179±35 −172±42 −144±42 0.29 −44±17 −75±22 −57±22 <0.0001 Peak Strain −20±3 −20±3 −20±3 0.49 −8±2 −14±4 −12±3 <0.0001

Conclusion

LV septal myectomy is followed by structural and functional remodelling which is more extensive in the right than the left ventricle. The clinical significance of these findings needs further study.

Characterization of size, shape and pattern of flow in the neo-aorta and pulmonary artery in a patient following an innovative technique of repair for truncus arteriosus

Background. Truncus arteriosus (TA) caries a very poor prognosis. In the absence of early correction, only 12 percent of patients born with this anomaly survive beyond one year. There is no agreement about the best method of surgical correction of this anomaly. We have devised an innovative valveless technique using autologous arterial tissue to repair TA.

Objectives. Characterizing the size, shape and pattern of flow in the neo-aorta and pulmonary artery, in a patient following the new technique.

Patient and Methods. Cardiac MRI and multislice CT imaging, followed by offline computerized image analysis was used in a patient aged 3 months, within 3 weeks of operating.

Results. The size, shape and topology of the neo-aorta and pulmonary artery, approximated that present in normal hearts. The pattern of flow in the reconstructed vessels was laminar, throughout the cardiac cycle with minor acceleration during systole. The pulmonary regurgitation resulting from the absence of a valve occurred during late diastole, and was well tolerated. The size of the right ventricle diminished considerably following operation, and the right ventricular ejection fraction was supernormal.

Conclusion. This early study in one patient provides new unique data of the size, shape, topology and pattern of flow in the neo-aorta and pulmonary artery, which appear to approximate normality. The long-term results of this promising operation need to be studied.

Progression of arterial toursosity syndrome to multiple aneurysms: Role of defining aortic flow and biomechanics

Arterial tortuosity syndrome (ATS) is a rare aortopathy characterized by multiple areas of tortuosity, stenosis and aneurysms in large and mid-sized arteries. The management of this syndrome is challenging because its complexity and variability in presentation and progression require a thorough understanding of the biological and biomechanical changes that occur in the arterial system. Here we describe, for the first time, the progression of this disease diagnosed in a 3-year old girl and the use of modern imaging modalities including cardiac magnetic resonance (CMR) 4D Flow, 3D modeling, and computational fluid dynamic simulation to characterize the complex aortic flow and its biomechanics. The integration of these modalities with the clinical evaluation will help in our understanding of this disease and provide patient-specific management.

Giant left atrial appendage aneurysm compressing the left anterior descending coronary artery

Left atrial appendage aneurysm (LAAA) is a rare congenital structural heart disease. It is often diagnosed by echocardiography; however, other imaging modalities can add to its diagnosis and its potential effects on the surrounding structures. A 16-year-old boy presented with dyspnea and palpitation. Transthoracic echocardiography showed a large LAAA communicating with the LA through a narrow neck with impaired left ventricular (LV) systolic function. Multidetector cardiac tomography showed that the LAAA is compressing the left anterior descending artery. The LAAA was surgically resected followed by improvement of the LV systolic function.

DECAAF: Emphasizing the importance of MRI in AF ablation

Atrial fibrillation ablation is a complex and challenging procedure. Appropriate patient selection is the most critical step to ensure safe and successful atrial fibrillation ablation procedure. The DECAAF study (Delayed-Enhancement MRI Determinant of Successful Radiofrequency Catheter Ablation of Atrial Fibrillation) showed that atrial tissue fibrosis, as estimated by delayed enhancement magnetic resonance imaging, was independently associated with recurrent arrhythmia post atrial fibrillation ablation. Magnetic resonance imaging also detected left atrial volume and shape. Integrating the data provided by magnetic resonance imaging into the pre-procedural planning is crucial.

Evaluation of cardiac function by magnetic resonance imaging during the follow-up of patients with Kawasaki disease

BACKGROUND

Although histopathologic studies suggest persistent myocardial abnormalities after Kawasaki disease (KD), the long-term effects on cardiac function remain to be revealed. We investigated biventricular volumes, function, and the presence of myocardial fibrosis by cardiac magnetic resonance imaging during long-term follow-up of KD.

METHODS AND RESULTS

Sixty patients with a history of KD (mean age, 16.9 years; 67% men; median interval after KD onset, 11.6 years) and 20 healthy control subjects (mean age, 17.9 years; 55% men) 12 to 24 years of age underwent cardiac magnetic resonance imaging. Biventricular end-diastolic volume, end-systolic volume, stroke volume, and ejection fraction were determined. Volumetric measurements were indexed for body surface area. Late contrast enhancement was used to detect areas of myocardial fibrosis. Biventricular volumes and function did not differ significantly between patients and control subjects. There were also no significant differences between patients with and without a history of left ventricular dysfunction resulting from KD-associated myocarditis or between patients with and without coronary artery aneurysms. Only those with prior ischemic heart disease had a significantly lower left ventricular ejection fraction compared with unaffected KD cases (left ventricular ejection fraction, 51% versus 57%; P=0.012). Late contrast enhancement was observed in only 2 patients with severe coronary artery aneurysms and was typical for myocardial infarction.

CONCLUSIONS

In this cardiac magnetic resonance imaging study evaluating the cardiac function of patients with KD at long-term follow-up, we did not observe a difference in cardiac function between KD patients and control subjects, except for a subgroup of patients with ischemic heart disease as a result of severe coronary artery pathology.

Comparison of contrast enhanced magnetic resonance angiography with invasive cardiac catheterization for evaluation of children with pulmonary atresia

Complete assessment of the source of pulmonary blood supply and delineation of the anatomy of pulmonary arteries are essential for the management and prognostic evaluation of pulmonary atresia (PA) patients. Invasive cardiac catheterization is considered the gold standard imaging modality to achieve this. We investigated the role of contrast enhanced magnetic resonance angiography (MRA) to evaluate the pulmonary blood supply and the anatomy of the pulmonary arteries and compared this with cardiac catheterization in children with PA. We studied 20 children with PA. Median age was 2.5 years (range 6 months–13 years). All patients were examined with cardiac catheterization and contrast enhanced MRA, and the results of both modalities were compared. There was a complete agreement between both modalities in the detection of the main pulmonary artery morphology and determination of the confluence state of the central pulmonary arteries. There was an 88% agreement for patency of the ductus arteriosus and 66% for patency of the surgically placed shunt. There was a complete agreement between both techniques on determining the presence of collaterals more than 2.5 mm. Twenty-eight collaterals of less than 2.5 mm were detected only by contrast enhanced MRA. There was a strong correlation between both modalities in measuring the pulmonary arteries and collaterals diameter (P<0.001). Contrast enhanced MRA is a safe and accurate non-invasive technique to evaluate the pulmonary artery morphology and the sources of pulmonary blood supply in children with PA.

Recovery of right and left ventricular function after acute pulmonary embolism

AIM

To evaluate recovery of cardiac function after acute pulmonary embolism (PE).

MATERIALS AND METHODS

Routine breath-held computed tomography (CT)-pulmonary angiography was performed in patients with suspected PE to confirm or exclude the diagnosis of PE at initial presentation. Electrocardiogram (ECG)-triggered cardiac CT was performed to assess biventricular function. After 6 months, cardiac magnetic resonance imaging (MRI) was performed. In total, 15 consecutive patients with PE and 10 without were studied. A significant change in ventricular volume was defined as a >15% change in end-diastolic or -systolic volumes (EDV, ESV), and significant ventricular function improvement as a >5% increase in ejection fraction (EF) as based on reported cut-off values.

RESULTS

Right and left ventricular (RV and LV) EDV and ESV changed non-significantly (<1.3%) in the patients without PE, indicating good comparability of those values measured by CT and MRI. PE patients with baseline normal RV function (RVEF ≥ 47%) revealed a >5% improvement in the RVEF (+5.4 ± 3.1%) due to a decrease in the RVESV. Patients with baseline abnormal RV function showed a >5% improvement in the RVEF (+14 ± 15%) due to decreases in both the RVESV and RVEDV. Furthermore, the LVEDV increased in this latter patient group.

CONCLUSIONS

The present study demonstrated an improvement in RV function in the majority of patients with PE, independent of baseline RV function. The degree of RV and LV recovery was dependent on the severity of baseline RV dysfunction.

Pulmonary flow profile and distensibility following acute pulmonary embolism

OBJECTIVE

Proof of concept study evaluating CMR as screening tool for chronic thromboembolic pulmonary hypertension (CTEPH) in patients treated for acute pulmonary embolism (PE).

MATERIALS AND METHODS

Right and left ventricular function of 15 consecutive patients treated for PE and 10 consecutive patients in whom PE was excluded was estimated at baseline by cardiac CT and at 6 months follow-up by CMR. Additionally, during the follow-up visit, pulmonary artery (PA) hemodynamics were studied by CMR and the presence of pulmonary hypertension by echocardiography.

RESULTS

CT measured right ventricular ejection fraction (RVEF) was lower in patients with PE compared to patients without PE at time of diagnosis (median 47%, interquartile range 39-53 vs. 55%, 52-58; p = 0.014). After 6 months follow up, the RVEF between patients treated for PE and patients without PE were not statistically significant different (55%, 52-60 versus 54%, 51-57; p = 0.57), as were distensibility index (0.18 ± 0.18 versus 0.25 ± 0.18, p = 0.20), mean velocity (14.1 ± 3.9 cm/s versus 14.0 ± 2.5 cm/s, p = 0.81), peak velocity (86.5 ± 22 cm/s versus 89.6 ± 13 cm/s, p = 0.43) and time to peak PA blood flow velocity (142 ± 49 ms versus 161 ± 29 ms, p = 0.14). One patient was diagnosed with CTEPH and CMR revealed poor right systolic function, decreased PA distensibility and flow velocity, and a systolic notch in the PA flow profile consistent with persistent PA obstruction.

CONCLUSION

In this small series, right ventricular performance and PA flow profiles of patients treated for 6 months after PE are equivalent to those parameters in normal patients.

Delayed improvement of right ventricular diastolic function and regression of right ventricular mass after percutaneous pulmonary valve implantation in patients with congenital heart disease

BACKGROUND

Percutaneous pulmonary valve implantation (PPVI) has been introduced as therapy for right ventricular (RV) to pulmonary artery conduit dysfunction in patients with congenital heart disease. It has been shown that RV systolic function improved early after PPVI. The effects of PPVI on RV diastolic function and RV hypertrophy have not yet been studied.

PURPOSE

The objective of this study is to assess early and late changes in systolic and diastolic RV function and RV mass after PPVI.

MATERIALS AND METHODS

Fourteen patients underwent PPVI (7 male, median age 15 years). Cardiac magnetic resonance imaging was performed before and at 2 time points after PPVI (at 1 and 16 months). Right ventricular volume and systolic and diastolic function as well as RV mass were assessed.

RESULTS

At 1 and 16 months after PPVI, the RV mass decreased from 28.6 +/- 2.1 to 25.6 +/- 2.2 g/m(2) (P = .03) and to 22.3 +/- 2.1 g/m(2) (P = .002). E/A volume ratio increased from 1.91 +/- 0.4 to 2.6 +/- 0.4 (not significant [NS]) and to 3.3 +/- 0.4 (P = .01). E/A peak flow ratio increased from 1.34 +/- 0.14 to 1.48 +/- 0.16 (NS) and to 1.73 +/- 0.14 (P = .04). E-wave deceleration time increased from 142 +/- 25 to 160 +/- 27 milliseconds (NS) and to 211 +/- 26 milliseconds (P = .007). At 1 month, RV end-diastolic volume decreased from 124 +/- 8 to 113 +/- 8 mL (P = .01) and RV ejection fraction increased from 36% +/- 2% to 46% +/- 2% (P = .001) without further improvement at 16 months.

CONCLUSION

After PPVI, in contrast to rapid improvement of RV systolic function, the improvement of RV diastolic function is delayed. The reduction of RV mass appears to be the underlying mechanism for improvement of RV diastolic function. Long follow-up for patients with PPVI is recommended.