Sara Thorne

Coronary Artery Imaging in Grown Up Congenital Heart Disease Complementary Role of Magnetic Resonance and X-Ray Coronary Angiography

BACKGROUNDnThere is a high incidence of anomalous coronary arteries in subjects with congenital heart disease. These abnormalities can be responsible for myocardial ischemia and sudden death or be damaged during surgical intervention. It can be difficult to define the proximal course of anomalous coronary arteries with the use of conventional x-ray coronary angiography. Magnetic resonance coronary angiography (MRCA) has been shown to be useful in the assessment of the 3-dimensional relationship between the coronary arteries and the great vessels in subjects with normal cardiac morphology but has not been used in patients with congenital heart disease.nnnMETHODS AND RESULTSnTwenty-five adults with various congenital heart abnormalities were studied. X-ray coronary angiography and respiratory-gated MRCA were performed in all subjects. Coronary artery origin and proximal course were assessed for each imaging modality by separate, blinded investigators. Images were then compared, and a consensus diagnosis was reached. With the consensus readings for both magnetic resonance and x-ray coronary angiography, it was possible to identify the origin and course of the proximal coronary arteries in all 25 subjects: 16 with coronary anomalies and 9 with normal coronary arteries. Respiratory-gated MRCA had an accuracy of 92%, a sensitivity of 88%, and a specificity of 100% for the detection of abnormal coronary arteries. The MRCA results were more likely to agree with the consensus for definition of the proximal course of the coronary arteries (P<0.02).nnnCONCLUSIONSnFor the assessment of anomalous coronary artery anatomy in patients with congenital heart disease, the use of the combination of MRCA with x-ray coronary angiography improves the definition of the proximal coronary artery course. MRCA provides correct spatial relationships, whereas x-ray angiography provides a view of the entire coronary length and its peripheral run-off. Furthermore, respiratory-gated MRCA can be performed without breath holding and with only limited subject cooperation.

Repaired coarctation: a “cost-effective” approach to identify complications in adults

OBJECTIVESnThe study was done to determine the most cost-effective approach to follow adults after repair of coarctation of the aorta.nnnBACKGROUNDnRecoarctation and/or aneurysm formation following surgical repair or angioplasty for coarctation of the aorta carry a significant morbidity and mortality. Various screening tests to detect such complications are used, but little is known of their sensitivities and specificities; as a consequence, the most cost-effective approach to follow such patients is undefined.nnnMETHODSnRetrospective analysis was done on the sensitivity and specificity of symptomatology, physical examination, electrocardiogram, chest radiograph, exercise testing and transthoracic echocardiography to detect recoarctation and/or aneurysm formation in 84 adult patients following surgical repair or angioplasty of coarctation of the aorta, using magnetic resonance imaging (MRI) as the gold standard test.nnnRESULTSnEchocardiography had the highest sensitivity in detecting recoarctation (87%) and chest radiograph the highest sensitivity in detecting aneurysm formation (67%). Combined clinical visit and echocardiography had a high sensitivity for diagnosing recoarctation and/or aneurysm formation (97%), but performing a clinical visit and an MRI on every patient without any prior screening test emerged as the most cost-effective strategy.nnnCONCLUSIONSnThe most cost-effective approach to diagnose complications at the site of repair in patients after surgical repair or balloon angioplasty of coarctation of the aorta appears to be the combination of clinical assessment and MRI scan on every patient. If MRI resources are scant, performing a clinical assessment plus a transthoracic echocardiography and an MRI on patients with positive results is an acceptable alternative.

Amiodarone-Associated Thyroid Dysfunction Risk Factors in Adults With Congenital Heart Disease

BACKGROUNDnAmiodarone is widely used in adults with congenital heart disease, but no systematic study has been published on its effects on thyroid function in these patients. A retrospective study was performed to examine the frequency of amiodarone-associated thyroid dysfunction in adults with congenital heart disease and to identify any contributing factors.nnnMETHODS AND RESULTSnAll adults (16 to 60 years old) with congenital heart disease were identified from a database if they had no preexisting thyroid disease, had taken amiodarone for >/=6 months, and were currently followed up by 1 consultant (J.S.). Ninety-two patients were found and evaluated for thyroid status and cardiac complications. A case-control analysis was performed, with patients matched for duration of amiodarone therapy. Of the 92 patients (age, 34.9+/-10.2 years; range, 18 to 60 years), 36% developed thyroid dysfunction: 19 became hyperthyroid and 14 hypothyroid. Female sex and complex cyanotic heart disease were significant risk factors for developing thyroid dysfunction (odds ratios, 3.0 and 7.00; P=0.04 and 0.01, respectively). Previous Fontan-type surgery also appeared to be a risk factor for developing thyrotoxicosis (odds ratio, 4.0; P=0.17), and amiodarone >200 mg/d a risk factor for thyroid dysfunction (odds ratio, 4.0; P=0.60).nnnCONCLUSIONSnAmiodarone-associated thyroid dysfunction is common in adults with congenital heart disease. Women and those with complex cyanotic lesions are at particular risk, as patients may be who have had Fontan-type surgery or are taking >200 mg/d of amiodarone. Amiodarone should be used only when other antiarrhythmics are ineffective or contraindicated. Vigilance is required to detect and treat thyroid dysfunction.

Changing practice of cardiac surgery in adult patients with congenital heart disease

Objectives: To review 13 years’ data from a unit for grown ups with congenital heart disease (GUCH) to understand the change in surgical practice. Methods: Records were reviewed of patients over 16 years of age undergoing surgery between 1 January 1990 and 31 December 2002 in a dedicated GUCH unit. Patients with atrial septal defects were included but not those with Marfan’s syndrome or undergoing a first procedure for bicuspid aortic valves. Three equal time periods of 52 months were analysed. Results: Of 474 operations performed, 162 (34.2%) were repeat operations. The percentage of repeat operations increased from 24.8% (41 of 165) in January 1990–April 1994 to 49.7% (74 of 149) in September 1998–December 2002. Mortality was 6.3% (n u200a=u200a 30). The median age decreased from 25.4 years (interquartile range 18.7) in January 1990–April 1994 to 23.9 (interquartile range 17.3) in September 1998–December 2002 (p u200a=u200a 0.04). The proportion of patients with a “simple” diagnosis decreased from 45.4% (74 or 165) in January 1990–April 1994 to 27.5% (41 of 149) in September 1998–December 2002 (p u200a=u200a 0.013). Pulmonary valve replacements in operated tetralogy of Fallot increased from one case in January 1990–April 1994 to 23 cases in September 1998–December 2002 and conduit replacement increased from five cases to 17. However, secundum atrial septal defect closures decreased from 35 cases to 14 (p < 0.0001). The estimated cost (not including salaries and prosthetics) incurred by an adult patient with congenital heart disease was £2290 compared with £2641 for a patient undergoing coronary artery bypass grafting. Conclusion: Despite the impact of interventional cardiology, the total number of surgical procedures remained unchanged. The complexity of the cases increased particularly with repeat surgery. Nevertheless, the patients do well with low mortality and the inpatient costs remain comparable with costs of surgery for acquired disease.

Pregnancy in high risk cardiac conditions

Heart disease is present in 0.5–1% of all pregnant women and is the biggest killer of pregnant women in the developed world (fig 1). Surprisingly, there have been no signs of decline in this incidence over the past two decades (fig 2). In the UK, all maternal deaths (during pregnancy and within the first post partum year) are recorded and examined in detail every 3 years. Of the maternal cardiac deaths reported for the 2003–5 triennium, more than half were due to coronary artery disease, puerperal cardiomyopathy and aortic dissection (table 1).1 As in previous triennial reports, substandard care continues to be an important factor, and contributed to the woman’s death in more than a third of cases.nnnnFigure 1 nOverall death rates per million maternities UK, 2003–05. AFE, amniotic fluid embolism; CNS, central nervous system; VTE, venous thromboembolism. Adapted with permission from Saving mothers’ lives: reviewing maternal deaths to make motherhood safer. 7th report of the Confidential Enquiries into Maternal Deaths in the UK . London: Royal College of Obstetrics and Gynaecology, 2007.nnnnnnFigure 2 nIncrease in maternal death from cardiac disease in the UK (deaths/1u2009000u2009000 maternities).nnnnView this table:nnTable 1 Major causes of maternal death from cardiac disease; UK 2003–2005. Adapted from: Saving mothers’ lives: reviewing maternal deaths to make motherhood safer. 7th report of the Confidential Enquiries into Maternal Deaths in the UK. London: Royal College of Obstetrics and Gynaecology, 2007. nnThese conditions often present acutely and catastrophically in women with no known pre-existing disease. Rapid recognition of the acute presentation and appropriate management will improve their chances of survival. In addition, identifying risk factors for these conditions should flag up at risk patients for targeted ante- and post-natal care. Modifiable risk factors such as obesity and smoking appear particularly important for this group of women and are a growing public health problem. In addition, social deprivation and immigrant status are significant risk factors for maternal deaths of all causes, including heart disease, underscoring the need to improve access to health care for these vulnerable groups.nn### Death from ischaemic heart diseasennMaternal deaths from acute coronary syndromes (ACS) and ischaemic …

Percutaneous device closure of a pseudoaneurysm of the left ventricular wall

The percutaneous device closure of a left ventricular pseudoaneurysm is described in a 60 year old man with a history of myocardial infarction complicated by ventricular tachycardia and left ventricular aneurysm treated by coronary artery bypass grafting and aneursymectomy with ventricular tachycardia ablation. He subsequently developed a vast pseudoaneurysm of the left ventricle with New York Heart Association functional class II heart failure symptoms. The selection of the approach and type of device used to close the neck of the pseudoaneurysm are discussed.

Oxygenation in Patients With a Functionally Univentricular Circulation and Complete Mixing of Blood Are Saturation and Flow Interchangeable

BACKGROUNDnPerioperative management of patients with complete mixing of pulmonary and systemic blood centers on approximately equating pulmonary (Qp) and systemic (Qs) blood flow (Qp/Qs approximately 1). This empirically derived target is opposed by theoretical studies advocating a target Qp/Qs well below 1. We studied the cause of this persistent discrepancy.nnnMETHODS AND RESULTSnClassic theoretical studies have concentrated on maximizing 1 of many potential combination parameters of arterial oxygen content (CaO(2)) and systemic blood flow: total oxygen delivery (DO(2))=CaO(2)xQs. We defined useful oxygen delivery as the amount of oxygen above a notional saturation threshold (Sat(Thresh)): D(u)O(2)=carrying capacityx(SaO(2)-Sat(Thresh))xQs. Whereas DO(2) peaks at Qp/Qs ratios <1, D(u)O(2) peaks at higher Qp/Qs ratios, nearer to (or exceeding) 1. Systemic venous saturation (which mirrors tissue oxygen tension) peaks at Qp/Qs=1.nnnCONCLUSIONSnFirst, the standard model of single-ventricle physiology can be reexpressed in a form allowing analysis by differential calculus, which allows broader conclusions to be drawn than does computer modeling alone. Second, the classic measure DO(2) fails to reflect the fact that proportional changes in saturation and flow are not clinically equivalent. Recognizing this asymmetry by using D(u)O(2) can give a target Qp:Qs balance that better represents clinical experience. Finally, to avoid an arbitrary choice of Sat(Thresh), systemic venous oxygen saturation (SsvO(2)) may be a useful parameter to maximize: this occurs at a Qp/Qs ratio of 1. Attempts to increase DO(2) by altering Qp/Qs away from this value will inevitably reduce SsvO(2) and therefore tissue oxygenation. Oxygen delivery is far from synonymous with tissue oxygen status.

Global cardiac risk assessment in the Registry of Pregnancy and Cardiac disease: Results of a registry from the European Society of Cardiology

To validate the modified World Health Organization (mWHO) risk classification in advanced and emerging countries, and to identify additional risk factors for cardiac events during pregnancy.

Analytical Identification of Ideal Pulmonary-Systemic Flow Balance in Patients With Bidirectional Cavopulmonary Shunt and Univentricular Circulation Oxygen Delivery or Tissue Oxygenation?

Background— In the present study, we extended previous mathematical modeling work on patients with bidirectional cavopulmonary (“bidirectional Glenn”) anastomosis to assess the potential utility of several descriptors of oxygen status. We set out to determine which of these descriptors best represents the overall tissue oxygenation. We also introduce a new descriptor, So2min, defined as the lower of the superior and inferior vena cava oxygen saturations. Methods and Results— The application of differential calculus to a model of oxygen physiology of patients with bidirectional Glenn allowed simultaneous assessment of all possible distributions of blood flow and metabolic rate between upper and lower body, across all cardiac outputs, total metabolic rates, and oxygen-carrying capacities. When total cardiac output is fixed, although it may intuitively seem best to distribute flow to maximize oxygen delivery (total, upper body, or lower body), we found that for each variable, there are situations in which its maximization seriously deprives flow to the upper or lower circulation. In contrast, maximizing So2min always gives physiologically sensible results. If the majority of metabolism is in the upper body (typical of infancy), then oxygenation is optimized when flow distribution matches metabolic distribution. In contrast, if the majority of metabolism is in the lower body (typical of older children and during exercise), oxygenation is optimal when flows are equal. Conclusions— In patients with bidirectional cavopulmonary anastomosis, because there is a tradeoff between flow distribution and saturation, it is unwise to concentrate on maximizing oxygen delivery. Maximizing systemic venous saturations (especially So2min) is conceptually different and physiologically preferable for tissue oxygenation.

Prevalence of migraine in adults with cyanotic congenital heart disease.

OBJECTIVEnThere is an increased prevalence of patent foramen ovale in patients with migraine, leading to the suggestion that migraine is more common in patients with potential right-to-left shunts. The aim of this study was to investigate the prevalence of migraine in adults with large right-to-left shunts because of cyanotic congenital heart disease.nnnDESIGN AND PATIENTSnIn total, 29 cyanotic adult patients with congenital heart disease answered a questionnaire to determine the prevalence of migraine with or without aura. A total of 38 matched acyanotic patients with congenital heart disease served as controls. A subgroup of 18 acyanotic patients also underwent bubble contrast echocardiography to look for patent foramen ovale.nnnRESULTSnTwenty (69%) of the cyanotic patients had migraine, the majority 17 (59%) having migraine with aura. Twenty-two (58%) of the 38 acyanotic patients had migraine, of whom 16 (42%) had migraine with aura. Nine (50%) of the 18 acyanotic patients who consented to an echocardiogram had patent foramen ovale. Of those with patent foramen ovale, 8 (89%) had migraine and 6 (67%) had migraine with aura.nnnCONCLUSIONnThere is an increased prevalence of migraine with aura in both cyanotic and acyanotic patients with congenital heart disease. The high prevalence of migraine in acyanotic patients with congenital heart disease may be due to an increased prevalence of patent foramen ovale.