Microsphere embolisation as an alternative for alcohol in percutaneous transluminal septal myocardial ablation.

BACKGROUND: Percutaneous transluminal septal myocardial ablation using microsphere embolisation is a new interventional technique to treat patients with hypertrophic obstructive cardiomyopathy. METHODS AND RESULTS: In two patients, considered at high risk for myectomy, targeted septal perforators were occluded with microsphere embolisation instead of alcohol ablation to reduce left ventricular outflow gradient. In both cases the left ventricular outflow tract gradient was immediately reduced. No adverse events occurred. CONCLUSION: This is the first clinical experience with Embozene® Microspheres in the Netherlands as an alternative for alcohol septal ablation. In both cases it resulted in immediate improvement in the haemodynamics, without any adverse events.

Paradoxical effects of interatrial conduction delay in a hypertrophic cardiomyopathy patient in the long-term: time is a great healer.

We present a unique case where early proarrhythmic and late antiarrhythmic characteristics of interatrial conduction delay were observed during the long-term progression of HCM. Occurrence of AT constantly increased as the interatrial conduction delay became more prominent, while the P-wave width in sinus rhythm and the AT cycle length both showed an instantaneous increase in parallel. As the interatrial delay reached a critical point, the right and left atrial P-wave became virtually separated, as demonstrated by the findings of ECGs and echocardiography. This phenomenon resulted in the complete cessation of tachycardias.

Contrast echocardiography: mechanism of action, safety and clinical applications.

Since its initial description by Gramiak and Shah in 1968, contrast echocardiography has become an established practice world-wide. Microbubbles have the unique property of being pure intravascular tracers. The basic rationale behind bubble imaging is the characteristic responses to ultrasound power that results in enhanced ultrasound images from the blood pool. Therefore, whenever there is blood pool there is a potential application for contrast ultrasound. Clinical applications of contrast echocardiography have been vastly grown from diagnostic applications such as detection of a persistent foramen ovale to drug delivery. This article reviews the mechanism of action, safety and clinical applications of contrast echocardiography.

Potential of [11C]acetate for measuring myocardial blood flow: Studies in normal subjects and patients with hypertrophic cardiomyopathy.

BACKGROUND: Measuring the rate of clearance of carbon-11 labelled acetate from myocardium using positron emission tomography (PET) is an accepted technique for noninvasively assessing myocardial oxygen consumption. Initial myocardial uptake of [(11)C]acetate, however, is related to myocardial blood flow (MBF) and several tracer kinetic models for quantifying MBF using [(11)C]acetate have been proposed. The objective of this study was to assess these models. METHODS: Eighteen healthy subjects and 18 patients with hypertrophic cardiomyopathy (HCM) were studied under baseline conditions with [(11)C]acetate and [(15)O]water. Four previously reported methods, including single- and multi-tissue compartment models, were used to calculate MBF from the measured [(11)C]acetate rate of influx K (1) and the (previously) reported relationship between K (1) and MBF. These MBF values were then compared with those derived from corresponding [(15)O]water studies. RESULTS: For all models, correlations between [(11)C]acetate and [(15)O]water-derived MBF ranged from .67 to .86 (all P < .005) in the control group and from .73 to .85 (all P < .001) in the HCM group. Two out of four models systematically underestimated perfusion with [(11)C]acetate, whilst the third model resulted in an overestimation. The fourth model, based on a simple single tissue compartment model with spillover, partial volume and recirculating metabolite corrections, resulted in a regression equation with a slope of near unity and an Y-intercept of almost zero (controls, K(1) = .74[MBF] + .09, r = .86, SEE = .13, P < .001 and HCM, K(1) = .89[MBF] + .03, r = .85, SEE = .12, P < .001). CONCLUSION: [(11)C]acetate enables quantification of MBF in fairly good agreement with actual MBF in both healthy individuals and patients with HCM. A single tissue compartment model with standardized correction for recirculating metabolites and with corrections for partial volume and spillover provided the best results.

Influence of the pattern of hypertrophy on left ventricular twist in hypertrophic cardiomyopathy.

BACKGROUND/OBJECTIVE: Left ventricular (LV) twist has an important role in LV function. The influence of the pattern of LV hypertrophy on LV twist in hypertrophic cardiomyopathy (HCM) patients is unknown. This study sought to assess LV twist in a large group of HCM patients according to the pattern of LV hypertrophy. METHODS: The final study population consisted of 43 patients with HCM (mean age 43 (15) years, 31 men) and a typical sigmoidal (n = 16) or reverse septal curvature (n = 27) and 43 age-matched and gender-matched healthy control subjects. LV peak systolic rotation (Rot(max)), LV peak systolic twist (Twist(max)) and untwisting at 5%, 10% and 15% of diastole were determined by speckle tracking echocardiography (STE). RESULTS: Compared to control subjects, HCM patients had increased basal Rot(max) (-5.5 degrees (2.3 degrees ) vs -3.4 degrees (1.7 degrees ), p<0.001) and comparable apical Rot(max) (7.3 degrees (3.1 degrees ) vs 7.0 degrees (2.2 degrees ), p = NS), resulting in increased Twist(max) (12.4 degrees (4.0 degrees ) vs 9.9 degrees (2.7 degrees ), p<0.01). Untwisting at 5%, 10% and 15% of diastole was decreased in HCM patients (all p<0.05). There was a striking difference in apical Rot(max )(9.4 degrees (2.8 degrees ) vs 6.0 degrees (2.6 degrees ), p<0.01) and Twist(max) (15.3 degrees (3.2 degrees ) vs 10.6 degrees (3.3 degrees ), p<0.01) between HCM patients with a sigmoidal and reverse septal curvature. CONCLUSIONS: STE may provide novel non-invasive indices to assess LV function in patients with HCM. Apical Rot(max) and Twist(max) in HCM patients are dependent on the pattern of LV hypertrophy.

A microcosting study of diagnostic tests for the detection of coronary artery disease in The Netherlands.

OBJECTIVE: The primary aim of the present study was to calculate the actual costs of four diagnostic tests for the detection of coronary artery disease in the Netherlands using a microcosting methodology. As a secondary objective, the cost effectiveness of eight diagnostic strategies was examined, using microcosting and reimbursement fees subsequently as the cost estimate. DESIGN: A multicenter, retrospective cost analysis from a hospital perspective. SETTING: The study was conducted in three general hospitals in the Netherlands for 2006. INTERVENTIONS: Exercise electrocardiography (exECG), stress echocardiography (sECHO), single-photon emission computed tomography (SPECT) and coronary angiography (CA). RESULTS: The actual costs of exECG, sECHO, SPECT and CA were 33, 216, 614 and 1300 euro respectively. For all diagnostic tests, labour and indirect cost components (overheads and capital) together accounted for over 75% of the total costs. Consumables played a relatively important role in SPECT (14%). Hotel and nutrition were only applicable to SPECT and CA. Diagnostic services were solely performed for CA, but their costs were negligible (2%). Using microcosting estimates, exECG-sECHO-SPECT-CA was the most and CA the least cost effective strategy (397 and 1302 euro per accurately diagnosed patient). Using reimbursement fees, exECG-sECHO-CA was most and SPECT-CA least cost effective (147 and 567 euro per accurately diagnosed patient). CONCLUSIONS: The use of microcosting estimates instead of reimbursement fees led to different conclusions regarding the relative cost effectiveness of alternative strategies.

Dobutamine stress MRI versus threedimensional contrast echocardiography: It's all Black and White.

Dobutamine stress magnetic resonance imaging is considered the superior stress modality to detect wall motion abnormalities. In this report we demonstrate the strengths of a newly developed stress modality: dobutamine stress contrastenhanced real-time three-dimensional echocardiography. This stress modality may become a competitor of stress magnetic resonance imaging allowing fast acquisition and an unlimited number of left ventricular cross sections. Unfortunately, at the moment adequate imaging with stress realtime three-dimensional echocardiography is only possible in a minority of cardiac patients. (Neth Heart J 2008;16:217-8.).

Acute effects of alcohol septal ablation on systolic and diastolic left ventricular function in patients with hypertrophic obstructive cardiomyopathy.

OBJECTIVE: Hypertrophic obstructive cardiomyopathy (HOCM) often leads to heart failure, severe symptoms and death. Percutaneous transluminal septal myocardial ablation (PTSMA) by alcohol injection efficiently reduces left ventricular (LV) outflow tract pressure gradient and improves symptoms. We determined acute changes in haemodynamics and systolic and diastolic LV function after PTSMA. METHODS: In 17 consecutive patients with symptomatic HOCM referred for PTSMA, the target vessel was determined by myocardial contrast transthoracic echocardiography. An over-the-wire balloon was inflated in the target vessel and multiple 0.5-ml alcohol injections were performed. LV systolic and diastolic function was assessed by online pressure-volume loops obtained by conductance catheter at baseline and acutely after the procedure. RESULTS: In all patients except two, a single septal branch was treated using a total of 2.0 (0.5) ml ethanol per patient. The rest and post-extrasystolic gradient were significantly decreased after PTSMA (79 (38) to 14 (16) mm Hg and 130 (50) to 34 (33) mm Hg, respectively, both p<0.001). Ejection fraction decreased (78% (9%) to 67% (13%), p<0.001). Cardiac output, heart rate and stroke work were unchanged, but systolic and diastolic volume increased. End-systolic and end-diastolic pressure significantly decreased (166 (27) to 129 (26) mm Hg, p<0.001 and 25 (6) to 21 (7) mm Hg, p = 0.049, respectively). Significant rightward shift (p<0.001) and decreased slope (p = 0.041) of the end-systolic pressure-volume relation indicated reduced contractility, whereas diastolic stiffness, -dP/dt(MIN), and tau were significantly improved after the procedure. CONCLUSIONS: PTSMA acutely reduced systolic function but promptly improved diastolic function with maintained cardiac output and stroke work. Improved diastolic function and increased end-diastolic volume compensated for the systolic loss and resulted in maintained haemodynamics.

Cardiac involvement in adults with Pompe disease.

BACKGROUND: Glycogen storage disease type II or Pompe disease is a neuromuscular disorder caused by deficiency of lysosomal acid alpha- glucosidase. Classic infantile Pompe disease results in massive left ventricular (LV) hypertrophy and failure. Although Pompe disease is often included in the differential diagnosis of LV hypertrophy the true frequency of cardiac involvement in adults with Pompe disease is not known. METHODS: Forty-six consecutive adult patients (mean age 48 +/- 12, 22 men) with Pompe disease were included. Each patient underwent a clinical examination, electrocardiography, and rest and low-dose dobutamine (in 20 patients) two-dimensional echocardiography including contrast and tissue Doppler imaging. RESULTS: All patients had limited exercise tolerance; a rollator walking aid was used in seven patients (15%), a wheelchair in 13 patients (28%), and assisted ventilation in 14 patients (30%). Prior to this study, one patient was known with permanent atrial fibrillation, His-bundle ablation and a VVI pacemaker and another patient was known with fluid retention. The first patient had increased LV end-diastolic diameter, impaired LV ejection fraction, low systolic mitral annular velocities and diastolic dysfunction grade II. The patient with fluid retention was wheelchair bound and dependent on 24-h assisted ventilation and showed right ventricular and LV hypertrophy (septum 16 mm, posterior wall 15 mm). LV hypertrophy was not seen in any of the other patients. One woman of advanced age had isolated low systolic mitral annular velocities. Mean global systolic LV function, including contractile reserve, was not decreased in patients with Pompe disease. Eight patients (17%) had mild diastolic dysfunction grade I, related to hypertension in four and advanced age in seven. CONCLUSIONS: In adult patients with Pompe disease without objective signs of cardiac affection by 12-leads electrocardiography or physical examination, echocardiographic screening for LV hypertrophy seems not effective.

Is there alteration in aortic stiffness in Leber hereditary optic neuropathy?

PURPOSE: Leber hereditary optic neuropathy (LHON) is recognized as the most common cause of isolated blindness in young men. The current study was designed to test whether LHON as a mitochondrial disease is associated with vascular functional alterations characterized by aortic elastic properties during echocardiography. METHODS: A total of 19 patients with typical features of LHON aged 42+/-13 years (10 males) were included. Their results were compared to 19 age- and gender-matched healthy controls. Aortic stiffness index was calculated from the echocardiographically derived aortic diameters and the clinical blood pressure data. RESULTS: In this patient population, the point mutation was present in 3460G>A position in five cases, in 11778G>A position in five cases, and in 14484T>C position in nine patients. Diastolic aortic diameter (26.0+/-2.5 mm vs 28.4+/-4.1 mm, p<0.05) and aortic stiffness index (5.1+/-2.6 vs 12.0+/-7.9, p<0.05) were significantly increased in LHON patients compared to controls. CONCLUSIONS: Aortic stiffness can be increased in LHON disease, but further studies are warranted to confirm these findings in a larger LHON patient population with a more reliable method focusing on the pathophysiologic background.

Clinical usefulness of SonoVue contrast echocardiography: the Thoraxcentre experience.

Although other imaging techniques, such as magnetic resonance imaging and computer tomography, are becoming more and more important in cardiology, two-dimensional echocardiography is still the most used technique in clinical cardiology. Quantification of left ventricular function and dimensions is important because therapeutic strategies, for example implanting an ICD after myocardial infarction, are based on ejection fraction measurements. Because of the sometimes low quality of echocardiographic images we started to use an ultrasound contrast agent and in this article we describe our experiences with SonoVue, a second-generation contrast agent, over a threeyear period in the Thoraxcentre. (Neth Heart J 2007;15:55-60.).

Familial screening and genetic counselling in hypertrophic cardiomyopathy: the Rotterdam experience.

Hypertrophic cardiomyopathy (HCM) is a disease characterised by unexplained left ventricular hypertrophy (LVH) (i.e. LVH in the absence of another cardiac or systemic disease that could produce a similar degree of hypertrophy), electrical instability and sudden death (SD).Germline mutations in genes encoding for sarcomere proteins are found in more than half of the cases of unexplained LVH. The autosomal dominant inherited forms of HCM are characterised by incomplete penetrance and variability in clinical and echocardiographic features, prognosis and therapeutic modalities. The identification of the genetic defect in one of the HCM genes allows accurate presymptomatic detection of mutation carriers in a family. Cardiac evaluation of at-risk relatives enables early diagnosis and identification of those patients at high risk for SD, which can be the first manifestation of the disease in asymptomatic persons.In this article we present our experience with genetic testing and cardiac screening in our HCM population and give an overview of the current literature available on this subject. (Neth Heart J 2007;15:184-9.).

Coronary flow reserve in hypertrophic cardiomyopathy: relation with microvascular dysfunction and pathophysiological characteristics.

BACKGROUND.: The decrease in coronary flow reserve (CFR) in hypertrophic cardiomyopathy (HCM) predisposes to myocardial ischaemia, systolic dysfunction and cardiac death. In this study we investigate to which extent haemodynamic, echocardiographic, and histological parameters contribute to the reduction of CFR. METHODS.: In ten HCM patients (mean age 44+/-14 years) and eight heart transplant (HTX) patients (mean age 51+/-6 years) CFR was calculated in the left anterior descending coronary artery. In all subjects haemodynamic, echocardiographic and histological parameters were assessed. The relationship between these variables and CFR was determined using linear regression analysis. RESULTS.: CFR was reduced in HCM compared with HTX patients (1.6+/-0.7 vs. 2.7+/-0.8, p<0.01). An increase in septal thickness (p<0.005), indexed left ventricular (LV) mass (p<0.005), LV end-diastolic pressure (p<0.001), LV outflow tract gradient (p<0.05) and a decrease in arteriolar lumen size (p<0.05) were all related to a reduction in CFR. CONCLUSION.: In HCM patients haemodynamic (LV end-diastolic pressure, LV outflow tract gradient), echocardiographic (indexed LV mass) and histological (% luminal area of the arterioles) changes are responsible for a decrease in CFR. (Neth Heart J 2007;15:209-15.).

Cardiac abnormalities in adults with the attenuated form of mucopolysaccharidosis type I.

BACKGROUND: Cardiac involvement in mucopolysaccharidosis type I (MPS I) has been studied primarily in its most severe forms. Cardiac involvement, particularly left ventricular (LV) systolic and diastolic function, in the attenuated form of MPS I is less well known. METHODS: Cardiac function was prospectively investigated in 9 adult patients with the attenuated form of MPS I. All patients underwent 12-lead electrocardiography, 24 h Holter monitoring and two-dimensional echocardiography including tissue Doppler imaging (TDI). Eighteen age- and sex-matched healthy volunteers served as a control group. RESULTS: Aortic, mitral and tricuspid valve thickening was seen in, respectively, 5 (56%), 4 (44%) and 2 (22%) patients. Moderate mitral valve stenosis was seen in 1 patient and moderate aortic stenosis in 2 patients. All patients had mild-to-moderate aortic and mitral valve regurgitation and 6 patients (67%) had mild-to-moderate tricuspid valve regurgitation. Despite normal LV dimensions, ejection fraction and mass index, MPS patients had lower mean systolic mitral annular velocities (6.1 +/- 0.6 vs 9.1 +/- 1.4 cm/s, p < 0.01) compared to normal control subjects. Similarly, mean early diastolic mitral annular velocities were lower in MPS patients (7.8 +/- 0.9 vs 13.3 +/- 3.3 cm/s, p < 0.01). CONCLUSION: MPS I patients with the attenuated phenotype have not only valvular abnormalities but also LV diastolic and systolic abnormalities.

Wide spectrum of presentation and variable outcomes of isolated left ventricular non-compaction.

OBJECTIVES: To investigate diagnostic routes, echocardiographic substrates, outcomes and prognostic factors in patients with isolated ventricular non-compaction (IVNC) identified by echocardiographic laboratories with referral from specialists and primary care physicians. PATIENTS AND DESIGN: Since 1991, all patients with suspected IVNC were flagged and followed up on dedicated databases. Patients were divided into symptom-based and non-symptom-based diagnostic subgroups. RESULTS: 65 eligible patients were followed up for 6-193 months (mean 46 (SD 44). In 53 (82%) patients, IVNC was associated with variable degrees of left ventricular (LV) dilatation and hypokinesia, and in the remaining 12 (18%) LV volumes were normal. Diagnosis was symptom based in 48 (74%) and non-symptom based in 17 (26%) (familial referral in 10). The non-symptom-based subgroup was characterised by younger age, lower prevalence of ECG abnormalities, better systolic function and lower left atrial size, whereas the extent of non-compaction was not different. No major cardiovascular events occurred in the non-symptom-based group, whereas 15 of 48 (31%) symptomatically diagnosed patients experienced cardiovascular death or heart transplantation (p = 0.01, Kaplan-Meier analysis). Independent predictors of cardiovascular death or heart transplantation were New York Heart Association class III-IV, sustained ventricular arrhythmias and left atrial size. CONCLUSIONS: IVNC is associated with a broad spectrum of clinical and pathophysiological findings, and the overall natural history and prognosis may be better than previously thought. Adult patients with incidental or familial discovery of IVNC have an encouraging outlook, whereas those who have symptoms of heart failure, a history of sustained ventricular tachycardia or an enlarged left atrium have an unstable course and more severe prognosis.