Practical Assessment of Maternal Cardiovascular Risk in Pregnancy

Cardiovascular disease in pregnancy is the most common cause of maternal mortality in the developed world and an important cause of heart failure, stroke, and arrhythmia. As more children with congenital heart disease survive into adulthood, there is a more pressing need to understand the risks that pregnancy poses for these women. Pregnancy, labor, and delivery increase the hemodynamic stress on the cardiovascular system and place women with heart disease at increased risk of cardiovascular complications, which include heart failure and death. Systematic assessment of pregnancy risk in these women, ideally before conception, is essential in optimizing maternal and fetal outcomes. This article describes the process of assessing risk of pregnancy‐associated cardiovascular complications in women with structural heart disease. We review the current literature on pregnancy risk in women with complex congenital lesions, valvular heart disease, cardiomyopathy, and aortopathy, and suggest an approach to risk stratification. Based on a review of the literature, we report features that pose an increased risk of adverse maternal and fetal outcomes, which include poor maternal functional status; prior history of heart failure, arrhythmia, or cerebral vascular events; cyanosis; poor systemic ventricular function; and severe aortic or mitral stenosis. Pulmonary hypertension and Eisenmenger syndrome place women at exceedingly high risk for cardiovascular complications in pregnancy, including maternal and fetal death.     

Physical performance and physical activity in grown-up congenital heart disease.

AIM: To review exercise performance and exercise habits in patients with congenital heart disease (CHD). BACKGROUND AND METHODS: Physical exercise and physical activity has shown beneficial effects on the physical, psychological and social level in adult patients with cardiovascular disease. Favourable effects have also been documented in children with CHD. Exercise testing is preferentially performed on a treadmill in children, with the measurement of gas exchange. RESULTS: An overview of the literature showed that formal exercise testing has frequently documented reduced or suboptimal values for aerobic exercise performance in children with left-to-right shunts (atrial septal defect, ventricular septal defect), valvular heart disease and obstructive anomalies (aortic stenosis, pulmonary stenosis, coarctation of the aorta). Subnormal values for exercise tolerance have also been observed in patients with successfully repaired cyanotic heart disease (tetraology of Fallot, transposition of the great arteries, Fontan operation). An important contributing factor to the impaired exercise performance is the hypoactive lifestyle, as often observed in patients with CHD. This frequently results from parental or environmental overprotection. CONCLUSION: These patients should be stimulated to be physically active, unless medical restriction is imposed. Fortunately, this represents only a small fraction of the total number of congenital heart defects for which sports participation is allowed.     

Exercise testing in pediatric cardiology.

Exercise testing in pediatric patients differs in many aspects from the tests performed in adults. Diseases that are associated with myocardial ischemia are very rare in children. Their cardiovascular response to exercise presents different characteristics, particularly maximal heart rate and blood pressure response, which are essential in interpreting hemodynamic data. The main indications for exercise testing in children are evaluation of exercise capacity and identification of exercise-induced arrhythmias. There are many testing protocols, but the Bruce protocol is widely used in many pediatric cardiac centers. In this article the authors describe the main indications for exercise testing in children with congenital heart disease, the contraindications for exercise testing and the indications for terminating an exercise test.     

Exercise training in the management of cardiac failure and ischaemic heart disease

Advice regarding physical activity is an important part of the management of cardiovascular disease. In addition to its role in primary prevention, it is now clear that patients with established ischemic heart disease and cardiac failure can benefit from exercise training.     

Practice Guidelines of the Spanish Society of Cardiology for the management of cardiac disease in pregnancy

Maternal adaptation to pregnancy includes reproductive hormone interaction plasma, volume changes with an increase in total body water, vascular alterations with a decrease in systemic resistance and modifications associated with hypercoagulability. These explain, in part, the appearance of signs and symptoms, even in a normal pregnant woman, that are difficult to distinguish from those occurring in heart disease and why some cardiac abnormalities are not well tolerated during pregnancy. Cardiovascular abnormalities are considered the first non-obstetric cause of morbidity and mortality during pregnancy. Rheumatic and congenital heart diseases are currently the most frequent cardiopathy found in women of childbearing age, followed by hypertension, coronary artery disease and arrhythmia. Although pregnancy is well tolerated by most women with heart disease, there are some cardiovascular abnormalities which place the mother and the infant at extremely high risk: patients with congestive heart failure and severe cardiac dysfunction, pulmonary hypertension, cyanotic congenital heart disease, Marfan's syndrome, severe obstructive lesions of the left side of the heart, patients with prosthetic cardiac valves and antecedents of peripartum cardiomyopathy should be encouraged to avoid pregnancy and the interruption of pregnancy may be advisable in cases with great risk of disability or death. The most severe cardiopathies significantly increase the risk of fetal loss and the presence of a congenital cardiac abnormality in either parent increases the risk of congenital cardiac disease in the fetus. Medical care must be initiated early, prior to conception and women with cardiopathy should be informed of the possible risks of pregnancy to both the mother and fetus.     

Exercise Training for People Living With Fontan Circulation: An Underutilized Intervention

Surgical repair for children born with single-ventricle congenital heart disease, culminating in the Fontan operation, has resulted in dramatic improvements in survival; children born with these lesions are now typically expected to survive well into adulthood. Most, but not all, patients with Fontan circulation have reduced exercise capacity compared with the general population that, in turn, is associated with increased cardiovascular morbidity and mortality. The cause of reduced exercise capacity is multifactorial. A significant contributor is the absence of a subpulmonary ventricular pump, which limits preload and appropriate cardiac output augmentation to meet the increased metabolic demands that occur with exercise. Although in its infancy relative to adults with acquired heart disease, the evidence to date suggests that exercise interventions to improve exercise capacity and Fontan physiology in children and adults with Fontan circulation are safe, effective, and well tolerated. However, many knowledge gaps remain, including a detailed understanding of the unique physiological adaptations that occur, the optimal approach to exercise in this population, and the effectiveness of home-based interventions using telemedicine and remote physiological monitoring technologies. Furthermore, the long-term impact of such interventions on the Fontan-cardiovascular system, physical activity levels, health-related quality of life, and late cardiovascular morbidity and mortality are not well characterized. In this review, we outline the factors associated with reduced exercise capacity in persons with Fontan circulation, review the experience to date of dedicated interventions to improve exercise capacity, and highlight the current knowledge gaps in the field and priorities for further study.     

Kardiale Dyspnoe

Dyspnea is an important symptom in cardiovascular medicine, can be associated with numerous diseases and carries important prognostic information. A careful history and physical examination can provide important clues in patients with dyspnea of unknown origin. In addition, several non-invasive methods can be helpful during the diagnostic work-up including laboratory data, electrocardiography, echocardiography, lung function tests, radiologic examinations and cardiopulmonary exercise testing. In selected cases invasive procedures including left and right heart catheterization are indicated. Patients with chronic heart failure have dyspnea that can be assessed with cardiopulmonary exercise testing, correlates with ventilation inefficiency and predicts prognosis in these patients. Ischemic heart disease is another important cause of dyspnea, as well as arrhythmias or valvular heart diseases. Dyspnea alone or in combination with cyanosis can occur in patients with congenital heart disease with or without intracardiac shunt. With respect to the treatment of cardiac dyspnea the primary goal remains the treatment of the underlying disease.     

Perspective: cardiovascular disease in the postgenomic era--lessons learned and challenges ahead

Despite remarkable advances in medical therapeutics and technology over the last 40 yr, cardiovascular disease remains the leading cause of mortality in the United States. Elucidation of the human genome and the application of gene mapping techniques to kindreds harboring rare monogenic cardiovascular syndromes have provided fundamental insights into the pathogenesis of common cardiovascular diseases including hypertension, hypercholesterolemia, cardiomyopathy with and without conduction system disease, cardiac arrhythmias, and most recently congenital heart disease. These findings led to the unanticipated conclusion that common cardiovascular pathologies (e.g. cardiomyopathy, congenital heart disease, hypertension, cardiac arrhythmias) are united by association with distinct subsets of genes. In this review, the impact of these data on the molecular pathogenesis and development of future therapies for cardiomyopathy, congenital heart disease, and atherosclerosis are highlighted. In addition, the application and limitations of evolving genetic and genomic technologies to acquired and/or multigenic cardiovascular states including atherosclerosis and high density lipoprotein (HDL) metabolism is discussed.     

Congenital heart disease: the original heart failure syndrome.

Heart failure is characterised by a triad comprising cardiac abnormality, exercise limitation and neurohormonal activation. The 2% of the adult population who suffer with heart failure are known to derive both symptomatic and prognostic benefit from exercise and pharmacologic neurohormonal antagonism. The existence of heart failure has traditionally been considered in the context of ischaemic, hypertensive, valvular and myopathic disease but in this article we develop the argument that patients with congenital heart disease also manifest all the pathophysiological criteria that constitute the chronic heart failure syndrome. We discuss the inherent limitations to a purely anatomical approach to congenital heart disease, bring attention to the large and rapidly growing population of adults with this condition and conclude by calling for a therapeutic approach to congenital heart disease that is based on the heart failure paradigm.     

Complete congenital heart block. Its natural history and evolution]

This study describes the natural history and evolution of 67 patients with congenital auriculoventricular heart block admitted in the Instituto Nacional de Cardiología "Ignacio Chávez", Mexico, D.F. from 1944 to 1998. There were 35 (52%) females and 32 (47%) males, with mean follow up period of 93.7 +/- 104 months. Most of the patients were without structural cardiovascular disease (90%). The most frequent symptoms were dyspnea and syncope. Electrocardiograms showed a ventricular heart rate of 42.2 +/- 9 beats/minute. 85.7% of patients had a supra-Hisian complete heart block. In 31% of patients a pacemaker was implanted because syncope. Overall mortality was 4.4% and malignant ventricular arrhythmias were the principal contributors. Risk factors for mortality identified in this study were junctional escape rhythm lower than 50 beats/minute, inappropriate chronotropic response during exercise, R-R interval prolongation at night, enlargement of cardiac chambers, depressed left ventricular ejection fraction and prolonged QT interval. In all of these conditions we recommend permanent pacemaker implantation.     

Prevalence of cardiovascular risk factors in adults with congenital heart disease.

BACKGROUND: Empirical evidence indicates that patients with congenital cardiac anomalies may be prone to developing coronary heart disease. Although primary prevention of ischaemic heart disease in patients with congenital heart defects is important, data on the prevalence of cardiovascular risk factors in these patients are not available. The aims of this study are therefore to describe the prevalence of risk factors for coronary heart disease in a large sample of adults with congenital cardiac anomalies, and compare this with the prevalence in the general population. DESIGN: A retrospective analysis of computerized patient records. METHODS: At our outpatient clinic, all patients are examined by an advanced practice nurse and a congenital heart disease cardiologist. Data on smoking behaviour, sports participation, blood pressure, body mass index, and the diagnosis of diabetes are recorded systematically. Data on the general population were derived from national health surveys. RESULTS: In a 4-year period, we collected data on 1976 individual patients. Male patients had a significantly higher prevalence of smoking and elevated blood pressure, whereas women were less engaged in sports activities and were more often obese. In comparison with the general population, our patients reported less smoking and more participation in sports, but presented more often with hypertension or diabetes. Only 20.4% of men and 21.0% of women have a fully heart-healthy lifestyle, as they presented without any risk factor. CONCLUSION: A substantial number of patients had one or more cardiovascular risk factors. Therefore, primary prevention by strengthening educational efforts becomes critically relevant in patients with congenital heart disease, to avoid the additional burden of coronary events in this growing population of patients.     

Mitochondrial dynamics: Orchestrating the journey to advanced age

Aging is a degenerative process that unfortunately is an inevitable part of life and risk factor for cardiovascular disease including heart failure. Among the several theories purported to explain the effects of age on cardiac dysfunction, the mitochondrion has emerged a central regulator of this process. Hence, it is not surprising that abnormalities in mitochondrial quality control including biogenesis and turnover have such detrimental effects on cardiac function. In fact mitochondria serve as a conduit for biological signals for apoptosis, necrosis and autophagy respectively. The removal of damaged mitochondria by autophagy/mitophagy is essential for mitochondrial quality control and cardiac homeostasis. Defects in mitochondrial dynamism fission/fusion events have been linked to cardiac senescence and heart failure. In this review we discuss the impact of aging on mitochondrial dynamics and senescence on cardiovascular health. This article is part of a Special Issue entitled: CV Aging.     

Low-intensity exercise training delays heart failure and improves survival in female hypertensive heart failure rats

Exercise training improves functional capacity and quality of life in patients with heart failure. However, the long-term effects of exercise on mortality associated with hypertensive heart disease have not been well defined. In the present study, we investigated the effect of low-intensity exercise training on disease progression and survival in female spontaneously hypertensive heart failure rats. Animals with severe hypertension (16 months old) were treadmill trained (14.5 m/min, 45 min/d, 3 d/wk) until they developed terminal heart failure or were euthanized because of age-related complications. Exercise delayed mortality resulting from heart failure (P<0.001) and all causes (P<0.05) and transiently attenuated the systolic hypertension and contractile dysfunction observed in the sedentary animals but had no effect on cardiac morphology or contractile function in end-stage heart failure. Training had no effect on terminal myocardial protein expression of antioxidant enzymes, calcium handling proteins, or myosin heavy chain isoforms but was associated with higher cytochrome oxidase activity in cardiac mitochondria (P<0.05) and a greater mitochondrial content of cardiolipin, a phospholipid that is essential for optimal mitochondrial energy metabolism. In conclusion, low-intensity exercise training significantly delays the onset of heart failure and improves survival in female hypertensive heart failure rats without eliciting sustained improvements in blood pressure, cardiac function, or expression of several myocardial proteins associated with the cardiovascular benefits of exercise. The effects of exercise on cytochrome oxidase and cardiolipin provide novel evidence that training may improve prognosis in hypertensive heart disease by preserving mitochondrial energy metabolism.     

Management of Women With Congenital or Inherited Cardiovascular Disease From Pre-Conception Through Pregnancy and Postpartum: JACC Focus Seminar 2/5

Maternal morbidity and mortality continue to rise in the United States, with cardiovascular disease as the leading cause of maternal deaths. Congenital heart disease is now the most common cardiovascular condition encountered during pregnancy, and its prevalence will continue to grow. In tandem with these trends, maternal cardiovascular health is becoming increasingly complex. The identification of women at highest risk for cardiovascular complications is essential, and a team-based approach is recommended to optimize maternal and fetal outcomes. This document, the second of a 5-part series, will provide practical guidance from pre-conception through postpartum for cardiovascular conditions that are predominantly congenital or heritable in nature, including aortopathies, congenital heart disease, pulmonary hypertension, and valvular heart disease.     

Cardiovascular hemodynamics and exercise tolerance in thyroid disease.

The heart is an organ sensitive to the action of thyroid hormone, and measurable changes in cardiovascular performance are detected with small variations in thyroid hormone serum concentrations. Most patients with thyroid disease experience cardiovascular manifestations, and the most serious complications of thyroid dysfunction occur as a result of cardiac involvement. The increased metabolic state and oxygen consumption that occur in hyperthyroid patients require an increased supply of oxygen and removal of metabolic products from the periphery. This is accomplished by increasing the cardiac output to meet the needs of the periphery. Circulation time is decreased in hyperthyroid patients, and a lowered arterial resistance and increased venous resistance promote the return of blood to the heart. Thyroid hormones may significantly decrease the strength of respiratory and skeletal muscles and affect regulatory mechanisms of adaptation to incremental effort. In hyperthyroidism, cardiovascular exercise testing and analysis of respiratory gas exchange demonstrate low efficiency of cardiopulmonary function as well as impaired chronotropic, contractile, and vasodilatatory reserves, which are reversible when euthyroidism is restored. During exercise, the increment (delta) of minute ventilation (respiratory rate x tidal volume), and oxygen pulse (oxygen uptake per heart beat) are significantly lower in dysthyroidism versus euthyroidism. Especially in older patients with thyroid dysfunction, markedly reduced workload, delta ejection fraction, and delta heart rate, both at the anaerobic threshold as well as at maximal exercise, are observed. In thyrotoxicosis, mitochondria oxidative dysfunction during exercise mostly causes intracellular acidosis, whereas in hypothyroidism, inadequate cardiovascular support appears to be one of the principal factors involved. These abnormalities partly explain why subjects with dysthyroidism are intolerant to exertion. Thus, in thyroid disease, both cardiac structures and function may remain normal at rest, however impaired cardiovascular and respiratory adaptation to effort becomes unmasked during exercise.     

Pregnancy: maternal and fetal heart disease

Cardiac disorders complicate less than 1% of all pregnancies. Physiologic changes in pregnancy may mimic heart disease. In order to differentiate these adaptations from pathologic conditions, an in-depth knowledge of cardiovascular physiology is mandatory. A comprehensive history, physical examination, electrocardiogram, chest radiograph, and echocardiogram are sufficient in most cases to confirm the diagnosis. Care of women with cardiac disease begins with preconception counseling. Severe lesions should be taken care of prior to contemplating pregnancy. Management principles for pregnant women are similar to those for the non-pregnant state. A team approach comprised of a maternal fetal medicine specialist, cardiologist, neonatologist, and anesthesiologist is essential to assure optimal outcome for both the mother and the fetus. Although fetal heart disease complicates only a small percentage of pregnancies, congenital heart disease causes more neonatal morbidity and mortality than any other congenital malformation. Unfortunately, screening approaches for fetal heart disease continue to miss a large percentage of cases. This weakness in fetal screening has important clinical implications, because the prenatal detection and diagnosis of congenital heart disease may improve the outcome for many of these fetal patients. In fact, simply the detection of major heart disease prenatally can improve neonatal outcome by avoiding discharge to home of neonates with ductal-dependent congenital heart disease. Fortunately, recent advances in screening techniques, an increased ability to change the prenatal natural history of many forms of fetal heart disease, and an increasing recognition of the importance of a multidisciplinary, team approach to the management of pregnancies complicated with fetal heart disease, together promise to improve the outcome of the fetus with congenital heart disease.     

Exercise training during chronic beta blockade in cardiovascular disease

To determine whether cardioselective and nonselective beta-blocking agents impair exercise training effects in patients with cardiovascular disease, 50 subjects were evaluated. All were in a 3-times-weekly medically supervised outpatient exercise program for 3 months or longer. Treadmill exercise tests were done initially and at 3-month intervals. Eight patients were receiving atenolol, 23 propranolol, 3 timolol, 6 metoprolol, and 8 nadolol and 1 patient receiving timolol changed to atenolol and 1 receiving nadolol changed to propranolol. Treadmill test duration increased significantly (p less than 0.05), from 7.5 +/- 2.5 to 9.9 +/- 2.3 minutes, with exercise training. In 35 of the 50 subjects heart rate at rest decreased significantly (p less than 0.05) from 67.5 +/- 11.7 to 60.4 +/- 10.5 beats/min. The other 15 subjects were excluded from heart rate analysis because beta blockade was begun 1 to 2 weeks after the initial exercise test. It is concluded that exercise training effects (increase in exercise test duration and decrease in resting heart rate) can be achieved in patients with cardiovascular disease in the presence of both cardioselective and nonselective beta-blocking agents.     

Exercise and acute cardiovascular events placing the risks into perspective: a scientific statement from the American Heart Association Council on Nutrition, Physical Activity, and Metabolism and the Council on Clinical Cardiology

Habitual physical activity reduces coronary heart disease events, but vigorous activity can also acutely and transiently increase the risk of sudden cardiac death and acute myocardial infarction in susceptible persons. This scientific statement discusses the potential cardiovascular complications of exercise, their pathological substrate, and their incidence and suggests strategies to reduce these complications. Exercise-associated acute cardiac events generally occur in individuals with structural cardiac disease. Hereditary or congenital cardiovascular abnormalities are predominantly responsible for cardiac events among young individuals, whereas atherosclerotic disease is primarily responsible for these events in adults. The absolute rate of exercise-related sudden cardiac death varies with the prevalence of disease in the study population. The incidence of both acute myocardial infarction and sudden death is greatest in the habitually least physically active individuals. No strategies have been adequately studied to evaluate their ability to reduce exercise-related acute cardiovascular events. Maintaining physical fitness through regular physical activity may help to reduce events because a disproportionate number of events occur in least physically active subjects performing unaccustomed physical activity. Other strategies, such as screening patients before participation in exercise, excluding high-risk patients from certain activities, promptly evaluating possible prodromal symptoms, training fitness personnel for emergencies, and encouraging patients to avoid high-risk activities, appear prudent but have not been systematically evaluated.     

Exercise hypertension: an adverse prognosis?

We sought to clarify the prognostic importance of an “exaggerated” or “hypertensive” systolic blood pressure response to exercise during an exercise test. Studies evaluating the prognosis for cardiovascular events and cardiovascular mortality in those with hypertension during exercise testing were systematically reviewed. Fourteen studies were identified. Six studies were of healthy volunteers or hypertensives. Eight studies were in subjects with known or suspected heart disease. Without established heart disease, exercise hypertension predicted cardiovascular events and cardiovascular death. However, two of the six studies included a multivariate analysis; both demonstrated no independent association. Studies in subjects with known or suspected heart disease demonstrated that exercise hypertension predicted fewer cardiac events and lesser mortality or, after multivariate adjustment, no associated risk. In a healthy population, a higher exercise blood pressure may indicate hypertension or prehypertension, instead of normal vascular function, and an associated long-term adverse prognosis. In a population with a high burden of heart disease, the highest risk subjects with the most extensive cardiac disease may not be capable of generating pressure or workload to allow the manifestation of exercise systolic hypertension. By comparison, therefore, those with exercise hypertension have a better prognosis.     

Exercise and the Risk of Sudden Cardiac Death

Sports activity may precipitate acute fatalities in both adults and young competitive athletes with concealed heart diseases. However, the risk-benefit ratio of physical exercise differs among these two age groups. In adolescents and young adults, competitive physical exercise is associated with a significant increase of the risk of sudden death. Sports is not "per se" cause of the enhanced mortality in this age group; rather, it acts as a trigger of cardiac arrest in those athletes who are affected by silent cardiovascular conditions, mostly cardiomyopathy, premature coronary artery disease and congenital coronary anomalies, which predispose to life-threatening ventricular arrhythmias during physical exercise. In adults, on the other hand, physical activity can be regarded as a "two-edged sword": vigorous exertion increases the incidence of acute coronary events in individuals who did not exercise regularly, whereas habitual physical activity reduces the overall risk of myocardial infarction and sudden coronary death by preventing development of coronary artery disease and progression of coronary atherosclerotic lesions.