Normalization Of Left Ventricular Function Research Articles

What We Can Learn from "Super-responders".

This review discusses the state of the art of knowledge to help decision making in patients who are candidates for cardiac resynchronization therapy (CRT) and to analyze the long-term total and cardiac mortality, sudden death, and CRT with a defibrillator intervention rate, as well as the evolution of echocardiographic parameters in patients with a left ventricular (LV) ejection fraction of greater than 50% after CRT implantation. Owing to normalization of LV function in super-responders, the need for a persistent defibrillator backup is also considered.

Pitfalls in Echocardiography: Coarctation of the Aorta Presenting as Dilated Cardiomyopathy (DCM).

Purpose: The morphologic spectrum of aortic coarctation extends from discrete isthmic obstruction to tubular hypoplasia of the entire aortic arch. Neonates with coarctation frequently present with congestive heart failure and critically reduced perfusion of the descending aorta following ductal closure. During the recent years we observed several infants with coarctation who presented beyond the neonatal period with dilated cardiomyopathy (DCM). We reviewed our patients with coarctation to determine whether this presentation represents an exception or is relevant for the differential diagnosis of children with DCM. Materials and Methods: From 1/2001 to 12/2013 74 babies with isolated coarctation were diagnosed in our institution. 50 patients presented in the neonatal period and 24 patients beyond the first month. Results: 5/74 infants presented after the neonatal period with poorly contractile, dilated left ventricles. Echocardiographic detection of the coarctation was facilitated by application of the ductal view and by Doppler interrogation of the celiac artery revealing a significantly diminished systolic flow velocity. All patients underwent resection of the coarctation and end-to-end anastomosis ofthe aorta. Postoperative normalization of left ventricular function was observed within a median interval of 2 months. Conclusion: Coarctation of the aorta presenting as DCM accounted for 21 % of our infants with coarctation who presented beyond the neonatal period and 7 % of those in the first year of life. The stenosis was difficult to detect because of its distal location and normal configuration of the aortic arch. Isthmic coarctation should be included in the differential diagnosis of infants with DCM and requires careful examination of the isthmic region in these children.

Idiopathic accelerated idioventricular rhythm or ventricular tachycardia originating from the right bundle branch: unusual type of ventricular arrhythmia.

Accelerated idioventricular rhythm (AIVR) or ventricular tachycardia (VT) originating from the right bundle branch (RBB) is rare and published clinical data on such arrhythmia are scarce. In this study, we will describe the clinical manifestations, diagnosis, and management of a cohort of patients with this novel arrhythmia. Eight patients (5 men; median age, 25 years) with RBB-AIVR/VT were consecutively enrolled in the study. Pharmacological testing, exercise treadmill testing, electrophysiological study, and catheter ablation were performed in the study patients, and ECG features were characterized. All RBB-AIVR/VTs were of typical left bundle-branch block morphology with atrioventricular dissociation. The arrhythmias, which demonstrated chronotropic variability, were often isorhythmic with sinus rhythm and were accelerated by physical exercise, stress, and intravenous isoprenaline infusion. The rate of RBB-AIVR/VT varied from 45 to 200 beats per minute. Two patients experienced syncope, and 3 had impaired left ventricular function. Metoprolol was proven to be the most effective drug to decelerate the arrhythmia rate and relieve symptoms. Electrophysiology study was performed in 5 patients and the earliest activation with a sharp RBB potential was localized in the mid or distal RBB area. Catheter ablation terminated the arrhythmia with subsequent RBB block morphology during sinus rhythm. During follow-up, patients' symptoms were controlled with normalization of left ventricular function either on metoprolol or by catheter ablation. RBB-AIVR/VT is an unusual type of ventricular arrhythmia. It can result in significant symptoms and depressed ventricular function and can be successfully treated with catheter ablation.

Contractile reserve assessed by dobutamine test identifies super-responders to cardiac resynchronization therapy.

IntroductionIn this study, we sought to determine whether myocardial contractile reserve (CR) assessed by dobutamine stress echocardiography (DSE) can identify patients who experience nearly complete normalization of left ventricular (LV) function after the implantation of a cardiac resynchronization therapy (CRT) pacemaker.Material and methodsThe study group consisted of 55 consecutive patients with non-ischemic dilated cardiomyopathy, LV ejection fraction (LVEF) < 35%, and prolonged QRS complex duration, who were scheduled for CRT pacemaker implantation. The DSE (20 µg/kg/min) was performed in all patients. The CR assessment was based on a change in the wall motion score index (ΔWMSI) and ΔLVEF during DSE. Super-response was defined as an increase in LVEF to > 50% and reduction in left ventricular end-systolic dimension to < 40 mm 12 months following the CRT implantation.ResultsA total of 7 patients (12.7%) were identified as super-responders to CRT. When compared to non-super-responders, these patients had significantly higher values of the dobutamine-induced change in ΔWMSI (1.031 ±0.120 vs. 0.49 ±0.371, p < 0.01), and ΔEF (17.9 ±2.2 vs. 8.8 ±6.2, p < 0.01). Receiver operating characteristic analysis showed that dobutamine-induced changes in ΔWMSI ≥ 0.7 and ≥ 14% for ΔEF are the best discriminators for a super-response. Patients with ΔWMSI ≥ 0.7 and ΔEF ≥ 14% are significantly less often hospitalized (p < 0.01) for worsening of heart failure during 28.5 ±3.0 months of the follow-up.ConclusionsContractile reserve assessed by DSE can identify patients with dilated cardiomyopathy who are likely to experience near normalization of LV function following CRT.

The apical nipple sign: a useful tool for discriminating between anterior infarction and transient left ventricular ballooning syndrome

Even after coronary angiography, transient left ventricular ballooning syndrome (TLVBS) can be misdiagnosed as ST-elevation myocardial infarction (STEMI) caused by transient thrombotic occlusion of the left anterior descending artery, as the appearance of the left ventricular angiograms is often very similar. As prognosis and antithrombotic treatment of these two conditions differ widely, it is desirable to make a correct diagnosis as early as possible. Between January 1998 and August 2012, we identified 145 patients diagnosed with TLVBS in a single tertiary hospital, based on the Mayo criteria and (near) normalization of left ventricular function over weeks. For 119 of these patients, coronary and left ventricular angiograms were available for detailed study. In 27 (22.7%) patients, mid-ventricular ballooning was observed, with preserved contractility of the apex, while in 92 (77.3%) typical apical ballooning was seen, with extensive akinesis of the apex. In 28 of the patients with typical apical ballooning (30.4%), we observed the presence of a very small zone with preserved contractility in the most apical portion of the left ventricle. We coined this phenomenon 'apical nipple sign'. For comparison, we reviewed the left ventricular angiograms of 405 patients who had been treated for anterior STEMI by emergency percutaneous intervention on the left anterior descending artery in our hospital between February 2007 and October 2012. On careful review, the apical nipple sign was not seen in any of these. While discrimination between TLVBS and anterior STEMI is warranted as early as possible after admission, this is very difficult, especially in the majority of cases presenting with the classical apical ballooning phenotype. By observing the herein-described apical nipple sign, the attending physician can make the diagnosis of TLVBS with virtual certainty in almost one-third of cases.

Idiopathic giant subaortic left ventricular aneurysm causing extrinsic compression of left coronary circulation and right pulmonary artery

Introduction: Myocardial infarction, dilated cardiomyopathy, sarcoidosis, Chaga's disease and myocarditis are recognized causes of left ventricular (LV) aneurysm. Idiopathic LV aneurysms are rare and we describe here one of its rare presentation. Case report description: A 45 year male presented with exertional angina for the past 1 year, with acute exacerbation since one day. His electrocardiogram (ECG) showed ST depression in infero-lateral leads and elevation in lead aVR and V1. Troponin I was negative with cardiomegaly on chest radiograph. Echocardiogram showed enlarged LV with hypokinesia involving antero-lateral wall, LV ejection fraction was 35%. Additionally there was a narrow neck aneurysm arising from the LV outflow tract which was multilobulated and extended anterosuperiorly and laterally causing dynamic compression of right pulmonary artery (RPA). CT angiography also showed similar findings. Coronary angiogram showed severe external compression of left main coronary artery extending up-to mid part of left anterior descending artery and proximal part of left circumflex artery. Surgical aneurysmectomy was done which normalized the LV function on follow up, but residual aneurysm persists requiring a redo surgery. ![Figure][1] Figure 1 Discussion: Idiopathic LV aneurysm is rare, but well recognized. It usually presents as ventricular tachyarrhythmias or sudden cardiac death. In our patient a giant multilobulated subaortic aneurysm caused extrinsic compression of RPA and left coronary circulation leading to angina. Normalization of LV function at followup suggests relief of external compression of the coronaries. Conclusion: We present here the first case report of a large idiopathic subaortic left ventricular aneurysm causing extrinsic compression of left coronary circulation and RPA manifesting as coronary artery disease. [1]: pending:yes

Good Prognosis for Pericarditis With and Without Myocardial Involvement

Background— The natural history of myopericarditis/perimyocarditis is poorly known, and recently published studies have presented contrasting data on their outcomes. The aim of the present article is to assess the prognosis of myopericarditis/perimyocarditis in a multicenter, prospective cohort study. Methods and Results— A total of 486 patients (median age, 39 years; range, 18–83 years; 300 men) with acute pericarditis or a myopericardial inflammatory syndrome (myopericarditis/perimyocarditis; 85% idiopathic, 11% connective tissue disease or inflammatory bowel disease, 5% infective) were prospectively evaluated from January 2007 to December 2011. The diagnosis of acute pericarditis was based on the presence of 2 of 4 clinical criteria (chest pain, pericardial rubs, widespread ST-segment elevation or PR depression, and new or worsening pericardial effusion). Myopericardial inflammatory involvement was suspected with atypical ECG changes for pericarditis, arrhythmias, and cardiac troponin elevation or new or worsening ventricular dysfunction on echocardiography and confirmed by cardiac magnetic resonance. After a median follow-up of 36 months, normalization of left ventricular function was achieved in &gt;90% of patients with myopericarditis/perimyocarditis. No deaths were recorded, as well as evolution to heart failure or symptomatic left ventricular dysfunction. Recurrences (mainly as recurrent pericarditis) were the most common complication during follow-up and were recorded more frequently in patients with acute pericarditis (32%) than in those with myopericarditis (11%) or perimyocarditis (12%; P &lt;0.001). Troponin elevation was not associated with an increase in complications. Conclusions— The outcome of myopericardial inflammatory syndromes is good. Unlike acute coronary syndromes, troponin elevation is not a negative prognostic marker in this setting.

心臓再同期療法により左室機能が正常化した重症特発性拡張型心筋症の1 歳男児例

成人の薬物療法抵抗性心不全症例に対して，心臓再同期療法（CRT）の使用頻度は増加している．一方，小児に対する使用例は少なく，その有用性に関してはほとんど知られていない．本症例は生後3ヵ月まで良好であった体重増加が5ヵ月で不良となり，心エコーにて高度の左室機能低下と内腔拡大を認め，特発性拡張型心筋症（IDCM）と診断された．利尿薬・ACE阻害薬およびβ 遮断薬を含む薬物療法を開始したが，脳性ナトリウム利尿ペプチドBNPは3,550pg/mLから1,050pg/mLに中等度低下したものの，体重増加は改善しなかった．心不全症状は薬物療法に抵抗性で，左室壁運動のdyssynchronyが顕著であることから，1歳4ヵ月時に心外からの両心室DDDペーシングによるCRTを導入した．CRT開始後心不全症状は著明に改善し，10ヵ月後には体重増加およびBNPはともに正常となった．心エコーでは左室機能と内腔径は正常化し，dyssynchronyも改善を認めた．今回われわれは，薬物療法抵抗性心不全を呈したIDCMの1歳男児例で，CRTの劇的な効果を経験し報告する．IDCMを含む重症心不全小児に対して，左室dyssynchronyの早期発見とCRTの導入は，期待できる治療戦略となりうることが示唆された．

Reverse Takotsubo Cardiomyopathy Associated With the Consumption of an Energy Drink

A 24-year-old man presented to the emergency room with chest pain, acute respiratory failure, and palpitations shortly after the ingestion of small amounts of an energy drink in little cups one after another. He was afebrile, with frequent runs of supraventricular and ventricular tachycardia and underlying sinus tachycardia. The patient was treated with fluids and metoprolol but required intubation because of progressive hypoxia. Chest x-ray revealed bilateral fluffy pulmonary infiltrates. His ECG was free of ischemic changes, and an echocardiogram at that time showed hypokinesis of all basal left ventricular segments with apical sparing and an ejection fraction of 35% (Figure 1 and Movie I in the online-only Data Supplement). His troponin was mildly increased and serially measured brain natriuretic peptide was elevated at 8000 pg/mL. Figure 1. ECG recorded at admission showing sinus tachycardia and nonspecific T-wave inversion in leads I and aVL. After treatment with furosemide, nitroglycerine, heparin, and aspirin, the patient responded with clinical improvement of vital signs and chest x-ray. Episodes of agitation and delirium ensued, delaying extubation. Computerized tomography brain scan and electroencephalogram were negative, and toxicological testing demonstrated no cocaine, cannabis, or …

Predicting Hyperresponse Among Pacemaker‐Dependent Nonischemic Cardiomyopathy Patients Upgraded to Cardiac Resynchronization

Right ventricular (RV) pacing engenders left ventricular (LV) dyssynchrony and may diminish LV systolic function, promote adverse cardiac remodeling, and foster heart failure (HF). This process may be reversible in some pacemaker-dependent patients upgraded to cardiac resynchronization therapy (CRT). We examined the clinical characteristics of pacemaker-dependent patients who exhibit hyperresponse (i.e., normalization of LV function) with CRT upgrade. We identified 51 chronically RV-paced patients with no coronary artery disease, LV ejection fraction (EF) ≤ 35%, and severe HF symptoms who were upgraded to CRT-defibrillators (CRT-D). Echocardiograms were performed before and ≥6 months after CRT. Patients with follow-up LVEF ≥ 50% were deemed hyperresponders. Clinical outcomes of death, cardiac transplant, mechanical circulatory support, and HF hospitalizations were assessed. Fifteen patients were CRT hyperresponders; all demonstrated ≥15% relative LV end-systolic volume decrease. Hyperresponders had smaller baseline LV dimensions and shorter known cardiomyopathy duration than nonhyperresponders (P < 0.01). The best predictors of hyperresponse using receiver operating characteristic analysis were LV end-systolic dimension <48 mm (area under the curve [AUC] 0.92, P < 0.001), LV end-diastolic dimension <58 mm (AUC 0.86, P < 0.001), and cardiomyopathy duration <24 months (AUC 0.82, P < 0.001). No hyperresponders died, received a cardiac transplant, or required mechanical circulatory support during 42 ± 22 months follow-up, whereas 5 nonhyperresponders died, 2 underwent transplant, and 1 required an assist device (log rank P = 0.049). Among chronically RV paced patients who are upgraded to CRT-D, smaller baseline LV dimensions and shorter known cardiomyopathy duration predict hyperresponse. Hyperresponders have excellent long-term survival.

Early Detection of Anomalous Origin of Left Coronary Artery from the Right Pulmonary Artery After Successful Repair of Critical Coarctation of the Aorta

Left ventricular (LV) function is impaired by increased afterload in neonates with severe coarctation of the aorta, which may result in endocardial fibroelastosis. Repair of the coarctation usually solves the problem, with LV function normalizing after a few weeks. This report describes a patient who underwent successful repair of critical coarctation with normalization of LV function despite signs of endocardial fibroelastosis but with persisting elevation of cardiac troponin T. Cardiac catheterization showed the rare coincidence of anomalous origin of left coronary artery from the right pulmonary artery (ALCAPA) and coronary sinus orifice atresia with left superior vena cava.

Phlebotomies as a treatment of serious heart failure due to haemochromatosis: a case report.

Haemochromatosis is a disturbance in the iron metabolism leading to excessive accumulation of iron in various organs such as the liver, pancreas, joints, skin, pituitary, testes and heart, with the last mentioned leading to heart failure. In this report we describe a patient with serious heart failure, attributed to homozygosity for C282Y in the haemochromatosis (HFE) gene, in whom repetitive phlebotomies led to normalisation of left ventricular function. (Neth Heart J 2009;17:438-41.).

Inflammation in takotsubo cardiomyopathy: insights from cardiovascular magnetic resonance imaging

Takotsubo cardiomyopathy (TTC) is an increasingly recognised acute cardiac syndrome, whose underlying pathophysiological mechanisms remain unknown. Inflammation might play a role as this has been shown in endomyocardial biopsies. The aim of this study was to assess inflammatory parameters in patients with TTC using a comprehensive cardiovascular magnetic resonance imaging (CMR) approach. Thirty-seven patients with the suspected diagnosis of TTC underwent CMR. T2-weighted imaging to calculate the oedema ratio, T1-weighted imaging before and after contrast agent administration to calculate the global relative enhancement (gRE), and late gadolinium enhancement (LGE) imaging were performed. In 11 patients CMR revealed the diagnosis of myocardial infarction (n = 7; 19%) or myocarditis (n = 4; 11%) with typical patterns of LGE. In all other patients (n = 26; 70%), no LGE was detected consistent with the diagnosis of TTC. Of these, in 16 patients (62%) both inflammatory markers (oedema ratio and gRE) were elevated with concomitant pericardial effusion, indicating acute inflammation. Follow-up CMR after 3 months showed complete normalisation of left ventricular function and inflammatory parameters in the absence of LGE and pericardial effusion. This CMR study provides further insights into the pathophysiological mechanisms in TTC, supporting the contribution of an inflammatory process in the acute setting.

A case of ST-elevation and nystagmus--when coronary thrombosis is not to blame

We present the case of a post-menopausal female who, following a prolonged period of vomiting and diarrhoea, presented acutely with Wernicke's; encephalopathy, chest pain, ST-segment elevation and congestive cardiac failure associated with hypotension. Coronary angiography demonstrated no abnormality. Haemodynamics improved significantly in the short-term following intravenous thiamine replacement, with complete resolution of all ST-segment abnormalities and normalization of left ventricular function at six-week follow-up. Shoshin beriberi in the context of metabolic alkalosis, secondary to severe electrolyte depletion, is exceptional and is a differential diagnosis to be considered in all malnourished patients presenting with symptoms and signs suggestive of an acute coronary syndrome, especially those with a history of alcohol-dependence.

Patients with non-ischaemic dilated cardiomyopathy and hyper-responders to cardiac resynchronization therapy: characteristics and long-term evolution

In some patients with non-ischaemic dilated cardiomyopathy (NIDCM), left bundle branch block (LBBB), and severe cardiac failure, cardiac resynchronization therapy (CRT) has been shown to reverse almost completely left ventricular (LV) function. These patients thus eligible to be qualified 'hyper-responders' are exclusively recruited in patients with NIDCM. Evaluate proportion of 'hyper-responders' among patients with NIDCM and try to determine their profile before implantation of CRT. Consecutive patients with DCM [LV ejection fraction (LVEF) <35%, LV end-diastolic diameter >60 mm], sinus rhythm, LBBB, and New York Heart Association (NYHA) class III and IV implanted with a CRT were prospectively followed. Patients were considered 'hyper-responders' if they fulfilled after a minimum period of 6 months the following criteria: functional recovery (NYHA class I or II) and LVEF >or=50%. Among the 51 NIDCM patients, 11 (21.5%) were 'hyper-responders' following CRT (LVEF increased from 26 +/- 9 to 59 +/- 6%, P < 0.01). In the 40 (78.5%) remaining patients, there was no or minimal functional improvement and only a modest increase in LVEF from 21 +/- 9 to 26 +/- 12% (P = 0.03). Comparison between 'hyper-responders' and remaining patients showed that baseline parameters of 'hyper-responders' were less severely deteriorated. In a significant subset of patients with CRT for NIDCM, a 'complete' functional recovery associated with normalization of LV function was observed. This observation suggests that LBBB could be the causative factor of DCM in this subgroup of patients. There was not a unique discriminating factor at baseline between 'hyper-responders' and remaining patients.

Full recovery of Takotsubo cardiomyopathy (apical ballooning) in two days

Takotsubo cardiomyopathy (TTC) is a new clinical entity characterised by acute but rapidly reversible left ventricular systolic dysfunction. This case report demonstrates the unique finding of a complete normalization of left ventricular function in a patient with TTC in only 36 h documented by cardiac magnetic resonance imaging. To our best knowledge, this is the most rapid complete recovery of left ventricular apical ballooning reported, yet. Medical management of our patient included optimized antihypertensive therapy with intravenous administration of the α-1-adrenergic blocker urapidil and the ß-blocker bisoprolol in highest recommended doses. Although optimal management of TTC has not been established, α- and β-blockade may be beneficial for rapid recovery of TTC and may be protective against the recurrence of stress-related left ventricular dysfunction due to acute and sudden catecholamine excess.

Chest pain and reversible midventricular ballooning in a woman after witnessing sudden cardiac death: A possible variant of takotsubo cardiomyopathy

A 60-year-old woman presented to the emergency department with acute onset of severe chest pain. The pain started that morning, after witnessing the sudden cardiac death of a coworker. The electrocardiogram did not reveal evidence of ischemic ST segment deviations. Creatinine kinase was within the normal range but cardiac troponin T was elevated (2.24 μg/L). Coronary artery disease was ruled out by emergency coronary angiography. However, left ventricular angiography demonstrated an atypical midventricular ballooning with a reduced left ventricular ejection fraction of 40%. Figure 1A shows the end-systolic and Figure 1B the end-diastolic left ventricular angiogram on admission. Cardiac magnetic resonance imaging was performed the next day and revealed a complete normalization of left ventricular function (ejection fraction of 65%) without any sign of regional hypokinesis or ballooning (Figure 1C). In addition, myocardial scar formation was ruled out by delayed contrast enhancement imaging (Figure 1D). Figure 1) A End-systolic left ventricular angiogram on admission. B End-diastolic left ventricular angiogram on admission. C Cardiac magnetic resonance image revealing a complete normalization of left ventricular function without any sign of regional hypokinesis ... These clinical findings are compatible with a diagnosis of takotsubo cardiomyopathy (1). Classical takotsubo cardiomyopathy is characterized by transient left ventricular apical ballooning, chest pain, myocardial enzyme release and electrocardiographic abnormalities suggestive of an acute coronary syndrome without the significant angiographic coronary artery stenosis that often occurs in postmenopausal women (2). In our patient, the onset of chest pain was associated with witnessing an acute cardiac death. Left ventricular angiography revealed atypical midventricular ballooning, which is a variant of classical takotsubo cardiomyopathy that is increasingly being studied (3). The present case is unique because no electrocardiogram changes occurred, and the patient recovered quickly and completely within 18 h. Due to several atypical features in the disease course, it is believed that the present patient presented with a new variant of the widening disease spectrum of takotsubo cardiomyopathy.

Reversible impairment of coronary flow reserve in takotsubo cardiomyopathy: A myocardial PET study

The precise etiology of takotsubo cardiomyopathy remains unclear. The study of myocardial blood flow (MBF) and coronary flow reserve (CFR) by use of positron emission tomography might help in understanding this syndrome. Three postmenopausal women underwent adenosine/rest perfusion with nitrogen 13 ammonia and metabolism with fluorine 18 fluorodeoxyglucose positron emission tomography, coronary angiography, cardiac magnetic resonance, and echocardiography in the acute phase of takotsubo cardiomyopathy and at 3 months' follow-up, after normalization of left ventricular function. PET study was performed in 2 parts: the perfusion analysis with nitrogen ammonia and the metabolism of the heart using FDG. MBF and CFR were analyzed quantitatively in the acute phase and at follow-up. The images highlighted the impairment of tissue metabolism in the dysfunctioning left ventricular segments in the acute phase, mainly in the apical segments and progressively less in the medium segments. At the same time, a clear inverse metabolic/perfusion mismatch emerged, which normalized 3 months later. The quantitative analysis of MBF showed a reduction in the acute phase in apical segments in comparison to basal segments without differences between midventricular and basal segments. In the acute phase CFR proved to be reduced in apical versus basal segments. CFR impairment of apical segments recovered completely after 3 months. The acute phase of takotsubo cardiomyopathy is characterized by an inverse perfusion/metabolism mismatch with a reduction in CFR in the apical segments. However, the impairment of CFR and the reduction of metabolism in the apical segments recovered completely after 3 months.

Biphasischer Verlauf der linksventrikulären Funktion bei einer 22jährigen Patientin mit akuter Myokarditis

Two days before admission a 22-year-old woman developed general fatigue, nausea, headache and retrosternal pain. Physical examination was unremarkable. Erythrocyte sedimentation rate was increased to 20/48, C-reactive protein to 3.3 mg/dl, and there was evidence of myocardial damage (creatine kinase 609 U/l, creatine kinase-MB 42 U/l, troponine T 8.39 ng/ml); ST-segment elevations in I, II, III, aVF and V-V6 of the ECG. Echocardiography revealed clearly thickened myocardium, moderate but haemodynamically not significant pericardial effusion, as well as impaired left ventricular function. Antimyosin scintigraphy was very abnormal. Cardiac catheterization confirmed the left ventricular dysfunction, rise of left ventricular enddiastolic pressure to 17 mm Hg, and a markedly reduced cardiac output of 2.4 l/min. Myocardial biopsy showed severe myocarditis with marked myocytolysis and considerable lymphocytic infiltrations. Enteroviral RNA was demonstrated in the myocardium by polymerase chain reaction. The haemodynamics became normal within only 3 days. Myocardial biopsy after 6 months was unremarkable histologically and immunohistologically, and left ventricular function was also normal. However, while after a further 12 months myocardial biopsy remained normal and no virus was demonstrated, there was definite, though moderate, impairment in left ventricular function, indicating a dilated cardiomyopathy. Even when histological and immunohistological evidence of healing of an acute viral myocarditis has been achieved, with complete normalization of left ventricular function, a dilated cardiomyopathy may subsequently develop. The pathophysiological mechanism of this occurrence remains unknown.

Outcome After Mechanical Aortic Valve Replacement in Children and Young Adults

We asked whether aortic valve replacement using a mechanical prosthesis would allow normalization of left ventricular function and structure in children and young adults. We performed a clinical follow-up examination in 30 patients with aortic valve replacement at 25 years of age or younger, including conventional and tissue Doppler echocardiography and magnetic resonance imaging. Aortic valve replacement was performed at the median age of 14.3 years (range, 7.6 to 24.3 years) using a mechanical prosthesis (St. Jude Medical; median diameter, 23 mm; range, 17 to 27 mm). Indications were severe aortic stenosis in 6 of 30 patients, aortic regurgitation in 20 of 30 patients, or a combination of aortic stenosis and regurgitation (4 of 30 patients). Aortic valve replacement was a reoperation in 12 of 30 patients who primarily underwent aortic valvotomy at a median of 7.1 years (range, 1.0 to 11.3 years). In-hospital mortality was 0%. Follow-up was a median of 6 years (range, 1.2 to 14.5 years). Twenty-nine of 30 patients were in New York Heart Association functional class I without thromboembolic complications, cerebrovascular accidents, or major bleeding on oral anticoagulation. Left ventricular dilatation before aortic valve replacement was present in 20 of 30 patients but normalized in all but 4 patients on follow-up. Most patients showed a normal end-diastolic volume on magnetic resonance imaging, and 23 of 26 patients showed a normal left ventricular ejection fraction (median, 0.53; range, 0.33 to 0.75). Peak systolic strain of the left ventricular myocardium was a median of -13.3% (range, -0.5% to -31%), and was normal in 28 of 30 patients. Aortic valve replacement in children and young adults offers a good treatment option and may lead to normalization of left ventricular size and function in most patients.