[Show abstract][Hide abstract] ABSTRACT: Respiratory complications are common causes of morbidity and the need of repeated X-ray examinations after cardiac surgery. Ultrasound of the chest, including the lung parenchyma, has been recently introduced as a new tool to detect many pulmonary abnormalities. Despite this, the use of lung ultrasound (LUS) in adult and congenital cardiac surgery remains limited. In particular, lung ultrasound has been mainly used in the evaluation of pleural effusion (PLE), but no consensus exists on methods to quantify the volume of the effusion. Usefulness of LUS for the assessment of diaphragmatic motion in children has also been highlighted, but no clear recommendation exists regarding its routine use. Accuracy of LUS in detecting pulmonary congestion after adult cardiac surgery has been demonstrated, whereas studies in children are still scarce, and data on pneumothorax and lung consolidations are limited in the paediatric population. There are methodological and practicality issues regarding diagnostic protocols (i.e. image views and their sequential order) and instrumentation (transducers and their setting) used in different studies. It also remains unclear which practitioner-the cardiologist, intensivist, pulmonologist or the radiologist, should perform the examination. Cost analysis pertaining to extensive clinical application of lung ultrasound in cardiac surgery has never been performed. Guidelines and recommendations are warranted for a systematic and extensive use of this technique in cardiac surgery at different ages, as it could serve as a useful, versatile tool that could potentially decrease time, radiation exposure and costs.
Interactive Cardiovascular and Thoracic Surgery 11/2015; DOI:10.1093/icvts/ivv315 · 1.16 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The Fontan operation for single ventricle palliation consists of the creation of a complete cavopulmonary connection, usually by incorporating inferior vena caval flow into a pulmonary arterial circulation already receiving flow from the superior vena cava. In single ventricle palliated in this way, the anatomy is complex, and the pathophysiological complications are frequent; so, cardiac imaging is a key aspect of clinical surveillance. Common problems that echocardiography and MRI may disclose and characterise in the Fontan palliation of single ventricle include obstruction of systemic venous and pulmonary arterial flow, atrioventricular and semilunar valve dysfunction, unintended collateral flow patterns, ventricular dysfunction, aortic arch obstruction, interatrial obstruction, fenestration flow and patch leaks. Despite the broad scope of these modalities for detection of such problems, often no single imaging method is comprehensive in any given patient. Therefore, physicians must recognise the limitations of each modality, and circumvent these by application of suitable alternatives. New imaging tools are becoming available, which may ultimately prove to be of value in the Fontan circulation. Proper application of diverse new technologies such as four dimensional flow, computational fluid dynamics and three-dimensional printing will require critical evaluation in the single ventricle population.
[Show abstract][Hide abstract] ABSTRACT: Background:
Pediatric echocardiographic nomograms for systolic/diastolic functional indices are limited by small sample size and inconsistent methodologies. Our aim was to establish pediatric nomograms for mitral valve (MV) pulsed wave Doppler (PWD) and tissue Doppler imaging (TDI) velocities.
We performed PWD/TDI measurements of MV velocities and generated models testing for linear/logarithmic/exponential/square root relationships. Heteroscedasticity was accounted for by White test or Breusch-Pagan test. Age, weight, height, heart rate (HR), and body surface area (BSA) were used as independent variables in different analyses to predict the mean values of each measurement.
In all, 904 Caucasian Italian healthy children (age 0 days-17 years; 45.5% females; BSA 0.12-2.12m(2)) were prospectively studied. No individual variable provided equations with an acceptable coefficient of determination (R(2)) and even the inclusion of multiple variables in the model resulted in only a partial amelioration of the R(2). Higher R(2) were obtained for PWD-E deceleration time (0.53), septal (Se') and lateral (Le') MV-TDI e' velocity (Se': 0.54; Le': 0.55). Variability was higher at lower age and BSA. In older children patterns were more reproducible; however, the exclusion of neonates did not substantially improve the final models. The low R(2) hampered building of z-scores and calculation of estimated percentiles. Thus normative data have been presented as observed percentile according to age for all measurements.
We report normal ranges for PWD and TDI mitral velocities derived from a large population of Caucasian children. Variability of diastolic patterns especially at lower ages needs to be taken into account.
Journal of Cardiology 11/2015; DOI:10.1016/j.jjcc.2015.10.004 · 2.78 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background:
Quantifying resource utilization in the inpatient care of congenital heart diease is clinically relevant. Our purpose is to measure the investment of inpatient care resources to achieve survival in hypoplastic left heart syndrome (HLHS), and to determine how much of that investment occurs in hospitalizations that have a fatal outcome, the mortality-related resource utilization fraction (MRRUF).
A collaborative administrative database, the Pediatric Health Information System (PHIS) containing data for 43 children's hospitals, was queried by primary diagnosis for HLHS admissions of patients ≤21 years old during 2004-2013. Institution, patient age, inpatient deaths, billed charges (BC) and length of stay (LOS) were recorded.
In all, 11,122 HLHS admissions were identified which account for total LOS of 277,027 inpatient-days and $3,928,794,660 in BC. There were 1145 inpatient deaths (10.3 %). LOS was greater among inpatient deaths than among patients discharged alive (median 17 vs. 12, p < 0.0001). BC were greater among inpatient deaths than among patients discharged alive (median 4.09 × 10(5) vs. 1.63 × 10(5), p < 0.0001). 16 % of all LOS and 21 % of all BC were accrued by patients who did not survive their hospitalization. These proportions showed no significant change year-by-year. The highest volume institutions had lower mortality rates, but there was no relation between institutional volume and the MRRUF.
These data should alert providers and consumers that current practices often result in major resource expenditure for inpatient care of HLHS that does not result in survival to hospital dismissal. They highlight the need for data-driven critical review of standard practices to identify patterns of care associated with success, and to modify approaches objectively.
[Show abstract][Hide abstract] ABSTRACT: Objectives:
We hypothesized that hepatic injury in single-ventricle CHD has origins that predate the Fontan operation. We aimed to measure hepatic stiffness using ultrasound and shear wave elastography (SWE) in a bidirectional cavopulmonary connection (BCPC) cohort.
Subjects were prospectively recruited for real-time, hepatic, ultrasound-SWE for hepatic stiffness (kPa) and echocardiography. Doppler velocities, a velocity-time integral, flow volume, and resistive index, pulsatility index, and acceleration index were measured in celiac and superior mesenteric arteries, and in the main portal vein (MPV). Comparisons were made among subjects who had BCPC, subjects who were healthy, and a cohort of patients who had undergone the Fontan procedure.
Forty subjects (20 patients who had BCPC; 20 age- and gender-matched control subjects) were studied. The hepatic stiffness in BCPC was elevated, compared with that in control subjects (7.2 vs 5.7 kPa; P = .039). Patients who had BCPC had significantly higher celiac artery resistive index (0.9 vs 0.8; P = .002); pulsatility index (2.2 vs 1.7; P = .002); and systolic-diastolic flow ratio (10.1 vs 5.9; P = .002), whereas the superior mesenteric artery acceleration index (796 vs 1419 mL/min in control subjects; P = .04) was lower. An elevated resistive index (0.42 vs 0.29; P = .002) and pulsatility index (0.55 vs 0.35; P = .001) were seen in MPV, whereas MPV flow was reduced (137.3 vs 215.7 mL/min in control subjects; P = .036). A significant correlation was found for hepatic stiffness with right atrial pressure obtained at catheterization (P = .002). Comparison with patients who underwent the Fontan procedure showed patients who had BCPC had lower hepatic stiffness (7.2 vs 15.6 kPa; P < .001).
Hepatic stiffness is increased with BCPC physiology, and this finding raises concerns that hepatopathology in palliated, single-ventricle CHD is not exclusively attributable to Fontan physiology. Hepatic stiffness measurements using SWE are feasible in this young population, and the technique shows promise as a means for monitoring disease progression.
The Journal of thoracic and cardiovascular surgery 09/2015; DOI:10.1016/j.jtcvs.2015.09.079 · 4.17 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Stainless steel embolization coils (SSEC) have been used for over four decades for vascular occlusion. Recently, the safety of these coils in a magnetic resonance environment has been called into question, with important ramifications for thousands of patients with existing coils in place. We performed a retrospective chart review at five tertiary care pediatric centers evaluating all children and young adults with implanted SSEC who underwent magnetic resonance imaging (MRI). Data reviewed included demographics, coil implantation, MRI studies, and follow-up evaluations. Complications such as heating, discomfort, or device migration were specifically sought. Two hundred and ninety-seven patients with implanted SSEC underwent 539 MRI examinations. The median age at SSEC implantation was 2.3 years (1 week-23.2 years). The MRI studies were performed a median of 7.4 years (4 days-23.1 years) after implantation. No patients experienced any reported complications associated with their MRI examinations during the study or at median follow-up post-MRI of 4.8 years (1 day-23 years). In this large, retrospective review of patients with implanted SSEC undergoing MRI, there were no reported adverse events. These findings support the recent change by Cook Medical Inc. of their standard embolization coils from a designation of magnetic resonance unsafe to conditional.
[Show abstract][Hide abstract] ABSTRACT: Liver cirrhosis has been shown to affect cardiac performance. However cardiac dysfunction may only be revealed under stress conditions. The value of non-invasive stress tests in diagnosing cirrhotic cardiomyopathy is unclear. We sought to investigate the response to pharmacological stimulation with dobutamine in patients with cirrhosis using cardiovascular magnetic resonance.
Thirty-six patients and eight controls were scanned using a 1.5 T scanner (Siemens Symphony TIM; Siemens, Erlangen, Germany). Conventional volumetric and feature tracking analysis using dedicated software (CMR42; Circle Cardiovascular Imaging Inc, Calgary, Canada and Diogenes MRI; Tomtec; Germany, respectively) were performed at rest and during low to intermediate dose dobutamine stress.
Whilst volumetry based parameters were similar between patients and controls at rest, patients had a smaller increase in cardiac output during stress (p = 0.015). Ejection fraction increase was impaired in patients during 10 μg/kg/min dobutamine as compared to controls (6.9 % vs. 16.5 %, p = 0.007), but not with 20 μg/kg/min (12.1 % vs. 17.6 %, p = 0.12). This was paralleled by an impaired improvement in circumferential strain with low dose (median increase of 14.4 % vs. 30.9 %, p = 0.03), but not with intermediate dose dobutamine (median increase of 29.4 % vs. 33.9 %, p = 0.54). There was an impaired longitudinal strain increase in patients as compared to controls during low (median increase of 6.6 % vs 28.6 %, p < 0.001) and intermediate dose dobutamine (median increase of 2.6%vs, 12.6 % p = 0.016). Radial strain response to dobutamine was similar in patients and controls (p > 0.05).
Cirrhotic cardiomyopathy is characterized by an impaired cardiac pharmacological response that can be detected with magnetic resonance myocardial stress testing. Deformation analysis parameters may be more sensitive in identifying abnormalities in inotropic response to stress than conventional methods.
Journal of Cardiovascular Magnetic Resonance 07/2015; 17(1):61. DOI:10.1186/s12968-015-0157-6 · 4.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Interest in strain (ε) and strain rate (SR) for the assessment of pediatric left ventricular (LV) myocardial function has increased. However, the strengths and limitations of published pediatric nomograms have not been critically evaluated. A literature search was conducted accessing the National Library of Medicine using the keywords myocardial velocity, strain, strain rate, pediatric, reference values, and nomograms. Adding the following keywords, the results were further refined: neonates, infants, adolescents, range/intervals, and speckle tracking. Ten published studies evaluating myocardial velocities, ε, or SR nomograms were analyzed. Sample sizes were limited in most of these studies, particularly in terms of neonates. Heterogeneous methods-tissue Doppler imaging, two- and three-dimensional speckle tracking-were used to perform and normalize measurements. Although most studies adjusted measurements for age, classification by specific age subgroups varied. Few studies addressed the relationships of ε and SR measurements to body size and heart rate. Data have been generally expressed by mean values and standard deviations; Z scores and percentiles that are commonly employed for pediatric echocardiographic quantification have been never used. Reference values for ε and SR were found to be reproducible in older children; however, they varied significantly in neonates and infants. Pediatric nomograms for LV ε and SR are limited by (a) small sample sizes, (b) inconsistent methodology used for derivation and normalization, and (c) scarcity of neonatal data. Some of the studies demonstrate reproducible patterns for systolic deformation in older children. There is need for comprehensive nomograms of myocardial ε and SR involving a large population of normal children obtained using standardized methodology.
[Show abstract][Hide abstract] ABSTRACT: Cardiovascular magnetic resonance (CMR) offers quantification of phasic atrial functions based on volumetric assessment and more recently, on CMR feature tracking (CMR-FT) quantitative strain and strain rate (SR) deformation imaging. Inter-study reproducibility is a key requirement for longitudinal studies but has not been defined for CMR-based quantification of left atrial (LA) and right atrial (RA) dynamics.
Long-axis 2- and 4-chamber cine images were acquired at 9:00 (Exam A), 9:30 (Exam B) and 14:00 (Exam C) in 16 healthy volunteers. LA and RA reservoir, conduit and contractile booster pump functions were quantified by volumetric indexes as derived from fractional volume changes and by strain and SR as derived from CMR-FT. Exam A and B were compared to assess the inter-study reproducibility. Morning and afternoon scans were compared to address possible diurnal variation of atrial function.
Inter-study reproducibility was within acceptable limits for all LA and RA volumetric, strain and SR parameters. Inter-study reproducibility was better for volumetric indexes and strain than for SR parameters and better for LA than for RA dynamics. For the LA, reservoir function showed the best reproducibility (intraclass correlation coefficient (ICC) 0.94–0.97, coefficient of variation (CoV) 4.5–8.2 %), followed by conduit (ICC 0.78–0.97, CoV 8.2–18.5 %) and booster pump function (ICC 0.71–0.95, CoV 18.3–22.7). Similarly, for the RA, reproducibility was best for reservoir function (ICC 0.76–0.96, CoV 7.5–24.0 %) followed by conduit (ICC 0.67–0.91, CoV 13.9–35.9) and booster pump function (ICC 0.73–0.90, CoV 19.4–32.3). Atrial dynamics were not measurably affected by diurnal variation between morning and afternoon scans.
Inter-study reproducibility for CMR-based derivation of LA and RA functions is acceptable using either volumetric, strain or SR parameters with LA function showing higher reproducibility than RA function assessment. Amongst the different functional components, reservoir function is most reproducibly assessed by either technique followed by conduit and booster pump function, which needs to be considered in future longitudinal research studies.
Journal of Cardiovascular Magnetic Resonance 05/2015; 17(1):36. DOI:10.1186/s12968-015-0140-2 · 4.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Our purpose was to evaluate yield of tools commonly advocated for surveillance of tetralogy of Fallot (TOF).
All patients (pts) with TOF, seen at any time from 1/2008 to 9/2013 in an academic cardiology practice were studied. At the first and each subsequent outpatient visit, the use of tools including history and physical (H&P), ECG, Holter (HOL), echocardiogram (Echo), MR or CT (MR-CT) and stress testing (STR) were noted. Recommendations for intervention (INT) and for time to next follow-up were recorded; rationale for each INT with attribution to one or more tools was identified.
There were 213 pts (mean 11.5 years, 130 male) who had 916 visits, 123 of which (13.4%) were associated with 138 INTs (47 surgical, 54 catheter-mediated, 37 other medical). Recommended follow-up interval was 9.44±6.5 months, actual mean follow-up interval was 11.7 months. All 916 (100%) patient visits had a H&P which contributed to 47.2% of INT decisions. Echo was performed in 652 (71.2%) of visits, and contributed to 53.7% of INTs. MR-CT was obtained in 129 (14.1%) of visits, and contributed to 30.1% of INTs. ECG was applied in 137 (15%) visits, and contributed to 1.6% of INTs. HOL was obtained in 188 (20.5%) visits, and contributed to 11.3% of INTs. STR was performed at 101 (11%) of visits, and contributed to 8.9% of INTs.
INTs are common in repaired TOF, but when visits average every 11-12 months, most visits do not result in INT. H&P, Echo and HOL were the most frequently applied screens, and all frequently yielded relevant information to guide INT decisions. STR and MR/CT were applied as targeted testing and in this limited, non-screening role had high relevance for INT. There was low utilisation of ECG and major impact on INT was not demonstrated. Risk stratification in TOF may be possible, and could result in more efficient surveillance and targeted testing.
[Show abstract][Hide abstract] ABSTRACT: The routine use of brain natriuretic peptide (BNP) in pediatric cardiac surgery remains controversial. Our aim was to test whether BNP adds information to predict risk in pediatric cardiac surgery.
In all, 587 children undergoing cardiac surgery (median age 6.3 months; 1.2-35.9 months) were prospectively enrolled at a single institution. BNP was measured pre-operatively, on every post-operative day in the intensive care unit, and before discharge. The primary outcome was major complications and length ventilator stay >15 days. A first risk prediction model was fitted using Cox proportional hazards model with age, body surface area and Aristotle score as continuous predictors. A second model was built adding cardiopulmonary bypass time and arterial lactate at the end of operation to the first model. Then, peak post-operative log-BNP was added to both models. Analysis to test discrimination, calibration, and reclassification were performed.
BNP increased after surgery (p<0.001), peaking at a mean of 63.7 h (median 36 h, interquartile range 12-84 h) post-operatively and decreased thereafter. The hazard ratios (HR) for peak-BNP were highly significant (first model HR=1.40, p=0.006, second model HR=1.44, p=0.008), and the log-likelihood improved with the addition of BNP at 12 h (p=0.006; p=0.009). The adjunction of peak-BNP significantly improved the area under the ROC curve (first model p<0.001; second model p<0.001). The adjunction of peak-BNP also resulted in a net gain in reclassification proportion (first model NRI=0.089, p<0.001; second model NRI=0.139, p=0.003).
Our data indicates that BNP may improve the risk prediction in pediatric cardiac surgery, supporting its routine use in this setting.
Clinical Chemistry and Laboratory Medicine 04/2015; DOI:10.1515/cclm-2014-1084 · 2.71 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objectives: To determine whether quantitative wall motion assessment by CMR myocardial feature tracking (CMR-FT) would reduce the impact of observer experience as compared to visual analysis in patients with ischemic cardiomyopathy (ICM).
Methods: 15 consecutive patients with ICM referred for assessment of hibernating myocardium were studied at 3 Tesla using SSFP cine images at rest and during low dose dobutamine stress (5 and 10 μg/kg/min of dobutamine). Conventional visual, qualitative analysis was per- formed independently and blinded by an experienced and an inexperienced reader, fol- lowed by post-processing of the same images by CMR-FT to quantify subendocardial and subepicardial circumferential (Eccendo and Eccepi) and radial (Err) strain. Receiver operator characteristics (ROC) were assessed for each strain parameter and operator to detect the presence of inotropic reserve as visually defined by the experienced observer.
Results: 141 segments with wall motion abnormalities at rest were eligible for the analysis. Visual scoring of wall motion at rest and during dobutamine was significantly different between the experienced and the inexperienced observer (p<0.001). All strain values (Eccendo, Eccepi and Err) derived during dobutamine stress (5 and 10 μg/kg/min) showed similar diagnostic accuracy for the detection of contractile reserve for both operators with no differences in ROC (p>0.05). Eccendo was the most accurate (AUC of 0.76, 10 μg/kg/min of dobutamine) parameter. Diagnostic accuracy was worse for resting strain with differences between oper- ators for Eccendo and Eccepi (p<0.05) but not Err (p>0.05).
Conclusion: Whilst visual analysis remains highly dependent on operator experience, quantitative CMR- FT analysis of myocardial wall mechanics during DS-CMR provides diagnostic accuracy for the detection of inotropic reserve regardless of operator experience and hence may improve diagnostic robustness of low-dose DS-CMR in clinical practice.
PLoS ONE 04/2015; 10(4):e0122858. DOI:10.1371/journal.pone.0122858 · 3.23 Impact Factor