Cardiac imaging and functional assessment in pregnancy

Acute Myocardial Infarction in Pregnancy

Cardiovascular disease, and particularly ischemic heart disease, is a leading cause of maternal morbidity and mortality in high-income countries. The incidence of acute myocardial infarction (AMI) has been rising over the past two decades due to increasing maternal age and a higher prevalence of cardiovascular risk factors in the pregnant population. Causes of AMI in pregnancy are diverse and may require specific considerations for their diagnosis and management. In this narrative review, we provide an overview of physiologic changes, risk factors, and etiologies leading to AMI in pregnancy, as well as diagnostic tools, reperfusion strategies, and pharmacological treatments for this complex population. In addition, we outline considerations for labor and delivery planning and long-term follow-up of patients with AMI in pregnancy.

Cardiovascular Testing and Imaging in Pregnant Women

Cardiovascular disease is a major contributor to maternal morbidity and mortality and frequently preventable. Women with known cardiovascular disease should undergo cardiac evaluation before pregnancy. Many women with pregnancy-associated cardiac complications are not previously known to have cardiac disease. Women at high risk or who have signs or symptoms suggestive of heart failure, angina, or arrhythmias should undergo prompt evaluation. This article describes various diagnostic imaging modalities that can be used in pregnancy, including indications, strengths, and limitations.

Evaluation and Diagnostic Testing

The evaluation of cardiovascular disease in pregnancy is challenging due to overlaps between cardiac and normal pregnancy symptomatology, as well as concerns about the potential impact, if any, of imaging studies on fetal development. We discuss here an approach to the evaluation of the pregnant cardiac patient and review the safety and utility of available diagnostic tests, including labs, electrocardiogram, echocardiography, stress testing, computed tomography, magnetic resonance imaging, and cardiac catheterization. Importantly, the majority of standard imaging studies can be safely performed in pregnancy, and a high index of suspicion must be maintained when evaluating pregnant patients, especially those with preexisting cardiovascular disease.

Is there a role for cardiac magnetic resonance imaging during pregnancy?

Purpose: To assess the role of cardiac magnetic resonance imaging (CMR) for the evaluation and management of women with cardiac disorders in pregnancy and postpartum.Methods: Retrospective record review of women at a university-affiliated, single institution referred for CMR without contrast due to known or suspected cardiac disorders between January 2010 and December 2015. Medical records, echocardiogram and CMR reports were reviewed. Instances where clinical management was changed based on CMR findings were identified.Results: There were 17 peripartum CMR studies performed without contrast in 17 pregnancies from 16 women. Indications for CMR included congenital heart disease (N = 8, 47.1%), Marfan syndrome or strong family history of Marfan syndrome (N = 5, 29.4%), cardiomyopathy (N = 1, 5.9%), cardiac mass (N = 1, 5.9%), persistent dyspnea with a normal echocardiogram (N = 1, 5.9%), and hypertension with suspected aortic root dilation (N = 1, 5.9%). CMR confirmed the echocardiogram diagnosis in eight (47.1%) and improved the diagnosis in five (29.4%). Availability of CMR findings changed the delivery management in 2/17 (11.8%) women. CMR was especially helpful in assessing the size of the aortic root in women at risk for dilation.Conclusions: Although echocardiogram imaging of the heart is considered the first-line method for assessing the maternal cardiac status, CMR can provide information about cardiac anatomy and function in pregnant women with complex cardiac disease or suspected aortic pathology. Management may be changed based on results.

Imaging of Cardiovascular Disease in Pregnancy and the Peripartum Period

OPINION STATEMENT

Cardiovascular disease is an important cause of morbidity and mortality during pregnancy and the postpartum period. During pregnancy, the cardiovascular system undergoes extensive hemodynamic, hormonal, and microstructural changes which may exacerbate a preexisting underlying cardiovascular condition or predispose to cardiovascular complications not typically seen in young healthy women. Such conditions include spontaneous coronary artery dissection, atherosclerotic coronary artery disease, and peripartum cardiomyopathy. When evaluating this patient population, the diagnostic strategy should be tailored to specifically assess this distinct disease spectrum. The choice of imaging techniques must also consider potential risks to both the mother and child; a unique challenge of diagnostic imaging during pregnancy. The risk of radiation from radiography, computed tomography, and nuclear medicine imaging; iodinated and gadolinium-based contrast media for computed tomography and magnetic resonance imaging respectively; and heat deposition from sonography are of special importance during pregnancy. A thorough understanding of pregnancy-specific cardiovascular complications and the capabilities and risks of available diagnostic imaging modalities is crucial to appropriately manage the pregnant patient.

Validation of maternal cardiac output assessed by transthoracic echocardiography against pulmonary artery catheterization in severely ill pregnant women: prospective comparative study and systematic review

OBJECTIVE

Most severe pregnancy complications are characterized by profound hemodynamic disturbances, thus there is a need for validated hemodynamic monitoring systems for pregnant women. Pulmonary artery catheterization (PAC) using thermodilution is the clinical gold standard for the measurement of cardiac output (CO), however this reference method is rarely performed owing to its invasive nature. Transthoracic echocardiography (TTE) allows non-invasive determination of CO. We aimed to validate TTE against PAC for the determination of CO in severely ill pregnant women.

METHODS

This study consisted of a meta-analysis combining data from a prospective study and a systematic review. The prospective arm was conducted in Pretoria, South Africa, in 2003. Women with severe pregnancy complications requiring invasive monitoring with PAC according to contemporary guidelines were included. TTE was performed within 15 min of PAC and the investigator was blinded to the PAC measurements. Comparative measurements were extracted from similar studies retrieved from a systematic review of the literature and added to a database. Simultaneous CO measurements by TTE and PAC were compared. Agreement between methods was assessed using Bland-Altman statistics and intraclass correlation coefficients (ICC).

RESULTS

Thirty-four comparative measurements were included in the meta-analysis. Mean CO values obtained by PAC and TTE were 7.39 L/min and 7.18 L/min, respectively. The bias was 0.21 L/min with lower and upper limits of agreement of -1.18 L/min and 1.60 L/min, percentage error was 19.1%, and ICC between the two methods was 0.94.

CONCLUSIONS

CO measurements by TTE show excellent agreement with those obtained by PAC in pregnant women. Given its non-invasive nature and availability, TTE could be considered as a reference for the validation of other CO techniques in pregnant women. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

RESUMEN OBJETIVO

Las complicaciones del embarazo más graves se caracterizan por trastornos hemodinámicos serios, debido a los cuales existe la necesidad de sistemas validados de monitorización hemodinámica para mujeres embarazadas. Aunque la cateterización de la arteria pulmonar (CAP) mediante termodilución es el patrón de referencia clínico para la medición del gasto cardíaco (GC), este método se usa con poca frecuencia debido a su naturaleza invasiva. La ecocardiografía transtorácica (ETT) permite la determinación no invasiva del GC. El objetivo de este estudio fue validar la ETT frente al CAP para determinar el GC en mujeres embarazadas gravemente enfermas. MÉTODOS: Este estudio consistió en un metaanálisis que combinó datos de un estudio prospectivo y una revisión sistemática. El estudio prospectivo se llevó a cabo en Pretoria (Sudáfrica) en 2003. Se incluyeron mujeres con complicaciones graves en el embarazo que requerían una monitorización invasiva mediante CAP según las directrices de ese momento. Se realizó una ETT en un plazo de 15 minutos de haber realizado el CAP y el investigador no tuvo acceso a las mediciones del CAP. Las mediciones comparativas se extrajeron de estudios similares obtenidos a partir de una revisión sistemática de la literatura y se añadieron a una base de datos. Se compararon las mediciones simultáneas del GC mediante ETT y CAP. La concordancia entre métodos se evaluó a través del método estadístico de Bland-Altman y de coeficientes de correlación intraclase (CCI).

RESULTADOS

Se incluyeron treinta y cuatro mediciones comparativas en el metaanálisis. Los valores medios del GC obtenidos mediante CAP y ETT fueron de 7,39 l/min y 7.18 l/min, respectivamente. El sesgo fue de 0,21 l/min, siendo los límites inferior y superior de la concordancia de -1,18 l/min y 1.60 l/min; el error porcentual fue del 19,1%, y el CCI entre ambos métodos fue de 0,94.

CONCLUSIONES

Las mediciones del GC en mujeres embarazadas mediante ETT muestran una excelente concordancia con las obtenidas mediante CAP. Dada su naturaleza no invasiva y su disponibilidad, la ETT podría considerarse como referencia para la validación de otras técnicas relacionadas con el GC en mujeres embarazadas. : ,。(pulmonary artery catheterization,PAC)(cardiac output,CO),,。(transthoracic echocardiography,TTE)CO。PACTTECO。 : meta。2003。PAC。PAC 15 minTTE,PAC。,。TTEPACCO。Bland-Altman(intraclass correlation coefficients,ICC)。 : meta34。PACTTECO7.39 L/min7.18 L/min。-1.18 L/min、1.60 L/min0.21 L/min,19.1%,ICC0.94。 : TTECOPACCO。,TTECO。.

Cardiac output and related haemodynamics during pregnancy: a series of meta-analyses

OBJECTIVE

Cardiac output, a fundamental parameter of cardiovascular function, has consistently been shown to increase across healthy pregnancy; however, the time course and magnitude of adaptation remains equivocal within published literature. The aim of the present meta-analyses was to comprehensively describe the pattern of change in cardiac output during healthy pregnancy.

METHOD

A series of meta-analyses of previously published cardiac output data during healthy, singleton pregnancies was completed. PubMed and Scopus databases were searched for studies published between 1996 and 2014. Included studies reported absolute values during a predetermined gestational age (non-pregnant, late first trimester, early and late second trimester, early and late third trimester, early and late postpartum). Cardiac output was measured through echocardiography, impedance cardiography or inert gas rebreathing. Observational data were meta-analysed at each gestational age using a random-effects model. If reported, related haemodynamic variables were evaluated.

RESULTS

In total, 39 studies were eligible for inclusion, with pooled sample sizes ranging from 259 to 748. Cardiac output increased during pregnancy reaching its peak in the early third trimester, 1.5 L/min (31%) above non-pregnant values. The observed results from this study indicated a non-linear rise to this point. In the early postpartum, cardiac output had returned to non-pregnant values.

CONCLUSION

The present results suggest that cardiac output peaks in the early third trimester, following a non-linear pattern of adaptation; however, this must be confirmed using longitudinal studies. The findings provide new insight into the normal progression of cardiac output during pregnancy.