Year : 2016 | Volume
: 9 | Issue : 1 | Page : 96--107
Pediatric cardiac sciences 2015: A summary of significant publications
Sangeetha Viswanathan1, Anil K Singhi2, Raman Krishna Kumar3,
1 Department of Pediatric Cardiology, MIOT International, Chennai, Tamil Nadu, India
2 Department of Pediatric Cardiology, Medica Superspecialty Hospital, Kolkata, West Bengal, India
3 Department of Pediatric Cardiology, Amrita Institute of Medical Sciences, Kochi, Kerala, India
Raman Krishna Kumar
Department of Pediatric Cardiology, Amrita Institute of Medical Sciences and Research Centre, Kochi - 682 041, Kerala
|How to cite this article:|
Viswanathan S, Singhi AK, Kumar RK. Pediatric cardiac sciences 2015: A summary of significant publications.Ann Pediatr Card 2016;9:96-107
|How to cite this URL:|
Viswanathan S, Singhi AK, Kumar RK. Pediatric cardiac sciences 2015: A summary of significant publications. Ann Pediatr Card [serial online] 2016 [cited 2021 May 12 ];9:96-107
Available from: https://www.annalspc.com/text.asp?2016/9/1/96/174342
This is an attempt to summarize all major publications in pediatric cardiology, pediatric cardiac surgery, anesthesia, and intensive care for the year 2015. The table does include two papers that appeared late in 2014. This selection is potentially useful for those who wish to do a quick overview of all articles that were published in the preceding year. Given the diversity of sources of literature in pediatric cardiac sciences, it is difficult to keep track of what is potentially useful.
The list is useful for fellows to select papers for in-depth reviews in journal clubs.
Four papers have been chosen for a detailed review as "Selected Summaries."
We would value critical feedback on what could have been additionally included and what perhaps did not merit inclusion in the list. This feedback can be sent to the editor via email.
Screening for rheumatic heart disease: Evaluation of a focused cardiac ultrasound approach. Mirabel M, Bacquelin R, Tafflet M, Robillard C, Huon B, Corsenac P, de Frémicourt I, Narayanan K, Meunier JM, Noël B, Hagège AA, Rouchon B, Jouven X, Marijon E2 Circ Cardiovasc Imaging. 2015 Jan;8(1).
Reason for choosing study: Public health impact.
Type of study: Prospective cohort study.
Study question: Can a nurse-led screening program using a handheld echo machine and simplified criteria (focused cardiac ultrasound or FCU) be effective as a screening tool in the detection of rheumatic heart disease (RHD)?
Background: RHD remains a public health problem in many parts of the developing world. Early detection aids secondary prevention by the administration of penicillin prophylaxis. Clinical examination remains poor in detecting RHD and detailed echocardiography by a cardiologist remains resource intensive in low-resource settings.
Aim: (i) To test the adequacy of the pocket echo machine in RHD surveillance, (ii) to assess the proficiency of nurses after brief training in carrying out FCU, (iii) to assess the sensitivity and specificity of using simplified echo criteria in detecting RHD in comparison with a detailed echocardiogram carried out by an experienced cardiologist (reference approach).
Methodology: A total of 1,217 school children were prospectively studied with focused cardiac ultrasound using a pocket-sized echo machine by nursing personnel guided by simplified echo diagnostic criteria to detect RHD. The criteria used were MR jet length >2 cm or the presence of AR. The mean age of the children was 9.6 ± 1 years with an equal male:female ratio.
The echo criteria were selected based on a preliminary study that looked at six different criteria in 189 children with and without RHD. A focused cardiac ultrasound (FCU) was performed using a V- scan (GE Medical Systems) handheld echo machine. Training of the two nurses involved 3 days of theoretical teaching and 30 hours of hands-on training along with tailored tutorship. The FCU performed by the nurses was compared with the detailed echocardiogram performed by the cardiologist (reference approach). Statistical analysis mainly focussed on the sensitivity, specificity, and interobserver variability of FCU.
Results and limitations: The overall sensitivity of this strategy was ~80% with a specificity of 90% thereby making it a possible way of RHD screening in low-resource settings. However, there need to be secondary prophylaxis programs in place to treat detected RHD. Also, there may be the problem of over detection leading to over treatment. However, this needs to be viewed in the public health context where more elaborate testing may be prohibitive in terms of cost and human resource.
Conclusion: This study suggests more large scale testing of this strategy before it can be implemented as a policy.
Comment: The study demonstrates the feasibility of task-shifting or task-sharing of a specific activity and is particularly suited for application in large-scale surveys in resource-constrained environments. In the past decade, there is increasing emphasis on echocardiography as a screening tool for "accurate" estimation of RHD disease burden. While it is true that RHD estimates by echocardiography tend to be substantially more than the clinically estimates, it is still not clear whether subclinical RHD needs treatment. Follow up studies are imperative and eagerly awaited. It is perhaps interesting to observe that selected regions of the world (e.g., Cuba and Costa Rica) have achieved a substantial reduction in RHD burden through strategies that have been implemented in the primary care settings. It is also increasingly clear that RHD burden is critically reflective of adequacy of primary care and robustness of health systems. Based on all evidence that we have, echocardiographic screening should not be considered a critical piece in RHD control.
Achievements in congenital heart defect surgery: A prospective, 40-year study of 7,038 patients. Erikssen G, Liestψl K, Seem E, Birkeland S, Saatvedt KJ, Hoel TN, Dψhlen G, Skulstad H, Svennevig JL, Thaulow E, Lindberg HL. Circulation. 2015;131:337-46.
Reason for choosing study: Study spans over 40 years; includes > 80% of children with CHD in Norway; has 98.5% complete follow-up data
Type of study: Retrospective cohort study.
Study question: What are the immediate and long-term outcomes of simple and complex surgery for congenital heart disease (CHD) over the last four decades in a tertiary referral hospital in Norway?
Background: The last few decades have seen remarkable advances in surgical techniques and postoperative care of patients with congenital heart disease. In addition, early detection along with concomitant advances in cardiac catheterization have improved both the survival and quality of life of patients with CHD.
Aim: To determine the overall trends in survival and freedom from re operation in congenital heart surgery over the last four decades.
Methodology: A total of 7,038 patients (<16 yrs) who underwent CHD surgery in Rikshospitalet, Oslo over last 4 decades were analyzed. The demographics, diagnosis, type of surgery, and outcomes were recorded. Fifty-three percent were classified as simple CHD and 41% were classified as complex, and the rest were miscellaneous.
Results and limitations: The number of patients undergoing surgery increased progressively whilst the age at operation decreased from a median of 1.6 year in 1971-1979 to 0.19 year in 2000-2011. There was a fall in the numbers of certain procedures due to the advent of cardiac catheterization and nonsurgical management of these lesions.
The outcome progressively improved with recent 1 year and 5 years survival rates of more than 95%. There was continuing improvement in 1-year survival even through the last decade (95.3% in 2005-2009 versus 99.6% in 2010-2011). The cumulative freedom from reoperation in complex CHD in the most recent decade was found to be ~75% at 5 years. This was despite increasing complexity of the primary surgery and is partly attributable to a significant decrease in palliative procedures. Long-term cumulative survival to 16 years of age also increased from 62% (1971-1989) to 87% (1990-2011).
Conclusion: The study showed highly significant, sequential, and continuing improvements in survival and reductions in reoperation after CHD surgery.
Comment: This study should be considered a benchmark for others to emulate. The exceptional results are reflective of an excellent comprehensive pediatric cardiac service from a country that has the highest human development index in the world.
The results of this study may not be applicable to many other parts of the world, specifically the low resource environments of low- and middle-income countries where an increasing number of operations are now being performed. The specific challenges here relate to poor preoperative condition, resource limitations for perioperative care and limitations in quality of follow-up care. However, these are standards worth aspiring for.
Breaking the limit: Mechanical characterization of overexpanded balloon expandable stents used in congenital heart disease. Bratincsak A, Moore JW, Gulker B, Choules B, Koren L, El-Said HG. Congenit Heart Dis. 2015;10:51-63.
Reason for choosing study: Study addresses the very important issue of the dilatability of stents in infants and young children with CHD.
Type of study: In vitro experimental study.
Study question: Can stents implanted in infants and children be serially dilated to significantly larger diameters without losing integrity and important mechanical characteristics?
Background: Intravascular stent implantation offers a relatively low-risk alternative to open heart surgery in young patients with congenital heart disease but a major limiting factor has been the 'inability' of routinely available stents to keep up with the somatic growth in infants and young children.
Aim: To assess the expansion potential of commonly used balloon expandable stents and to characterize the mechanical parameters of these stents at the maximum expansion diameter (MED).
Methodology: Sixteen types of commonly used stents were dilated 1.3-2.4 (mean 1.7) times the recommended diameter. For mechanical testing, all stents were expanded unconstrained in a 37°C ± 2°C water bath over an appropriately sized guide wire. The stent diameter during expansion was confirmed by laser micrometer measurements.
To test the mechanical parameters, the stents were dilated in a serial fashion: First, the stents were inflated to the MED, which is defined as the maximum diameter recommended by the respective manufacturers. Then, the stents were expanded beyond the MED using a series of noncompliant balloons in sequential increments of 2 mm until the stent fracture occurred. For each measurement, at least three stents (ranged from 3 to 7) were used, with a few exceptions.
Results and limitations: Stents could be dilated to an average of 1.7 times the NED (range from 1.3 to 2.4 times) without losing mechanical integrity. Cook and ev3 stents showed negligible length change at MED; however, significant change was demonstrated with Cordis and Atrium stents. The radial strength was found better at higher diameters and the stents were found to maintain good mechanical characteristics when dilated beyond their recommended NED.
These results support the use of balloon expandable stents in smaller vessels that require future serial redilation. The obvious limitation is the in vitro nature of the study.
Comment: Stents have become an indispensable tool for the pediatric cardiologists. The specific challenges in stents include overcoming technical challenges with deployment in small children and allowing for progressive increase in size as the child grows. Unfortunately, few stents are specifically manufactured for specific use in children with cardiovascular disease. Stents are primarily manufactured for peripheral vascular disease in adults and for locations outside the vascular system because this is a much larger market. This in vitro study specifically examines the effect of progressive dilation above the recommended maximum expansion diameter recommended for a number of commercially available stents and generates useful information on feasibility of dilation beyond MED, radial strength, and shortening. The variations in the constraining influence of surrounding structures when stents are implanted in vivo are likely to be considerable (from soft structures such as atrial septum to calcified rigid conduits). Therefore, the results of this study may not consistently apply to real-life implantations.
A new predictive equation for oxygen consumption in children and adults with congenital and acquired heart disease. Seckeler MD, Hirsch R, Beekman RH 3 rd , Goldstein BH. Heart. 2015;101:517-24.
Reason for choosing study: This study attempts to improve the existing Lafarge equation used to calculate oxygen consumption for estimation of cardiac output by Fick's principle.
Type of study: Retrospective followed by prospective validation.
Study question: Development of a new predictive equation for oxygen consumption (VO 2 ) in children and adults with congenital and acquired heart disease.
Background: Estimation of cardiac index and therefore pulmonary and systemic blood flow and vascular resistances relies on Fick's principle that routinely uses oxygen consumption data derived from the archaic Lafarge table that has not been validated in children aged <3 years and has been shown to be inaccurate in current day practice. Although it is theoretically possible to measure VO 2 (mVO 2 ) in every patient, this is cumbersome and time-consuming.
Aim: To identify factors associated with inaccuracies in assumed VO2 using the Lafarge equations, and more importantly, to develop and validate a new VO2 predictive equation for use in patients of all ages.
Methodology: The authors retrospectively evaluated 502 patients (0-59 yrs) who underwent cardiac catheterization with measured VO 2 (M-VO 2 ) and compared M-VO 2 with VO 2 from the LaFarge equations (LF-VO 2 ). The factors associated with the inaccuracy were analyzed and a new equation was derived. The new equation was prospectively tested in 100 patients and compared with M-VO 2 .
Results and limitations: LF-VO 2 was inaccurate in 42% of Group 1 (age <3 y; N = 201) and 13% of Group 2 (age ≥3 y; N = 301). The data varied in single ventricle and biventricular physiology. Multiple logistic regression identified younger age and single ventricle anatomy in Group 1 and anemia in Group 2 as significant predictors of an inaccurate LF-VO2; critical illness was of borderline significance in both groups.
A new equation was formulated as follows:
VO 2 = 242.1 + [9.7 × ln age] - [34 × ln weight] - [9.6 × single ventricle] - [11.2 × critical illness]
The VO 2 calculated with the new equation was comparable with the M-VO 2 . In the age group < 3 years the new equation proved more accurate than the Lafarge equation and in the group ≥3 years it was comparable in accuracy. The authors have also laid out tables with VO 2 values for single ventricle and biventricular groups based on their study data.
This study is limited by relatively small numbers from a single center particularly in the prospective validation phase. It will need further validation and if found to be reliable will be of great utility in modern day cardiac catheterization.
Comment: Notwithstanding the fact that assumptions in oxygen consumption is perhaps the most consistent source of error in calculations of flows and resistances in the catheterization laboratory, the Lafarge and Mittenen tables are still being used extensively. This study offers the prospect of improvements in the Lafarge tables but will need validation through a multi-institutional study.