Outcome of transcatheter atrial septal defect closure in a nationwide cohort.

BACKGROUND: Transcatheter (TC) atrial septal defect (ASD) closure has been the mainstay of therapy for secundum-type ASDs for over 20 years. AIMS: This nationwide cohort evaluated the long-term outcome of transcatheter-closed ASDs. METHODS: The study enrolled every transcatheter ASD closure performed in Finland from 1999 to 2019. Five age, sex, and municipality-matched controls per ASD patient were gathered from the general population. The median follow-up period was 5.9 years (range 0-20.8). We used the hospital discharge register to gather all hospital visits and diagnoses. Closure complications and echocardiographic changes were collected from the electronic health records. RESULTS: Transcatheter ASD closure was performed in 1000 patients (68.5% females) during the study period. The median (range) age at the time of the procedure was 37.9 (1.8-87.5) years. ASD patients had an increased risk for new-onset atrial fibrillation (RR 2.45, 95% CI: 1.84-3.25), migraine (RR 3.61, 95% CI: 2.54-5.14), ischemic heart disease (RR 1.73, 95% CI: 1.23-2.45), ventricular fibrillation/tachycardia (RR 3.54 (95% CI: 1.48-8.43) and AV conduction disorder (RR 3.60, 95% CI: 1.94-6.70) compared to the control cohort. Stroke risk was not increased (RR 1.36, 95% CI: 0.91-2.03). Adverse events occurred in 6.3% (n = 63) of the patients, including four erosions and ten device embolizations. CONCLUSION: After TC closure of ASD, patients had a higher risk of new-onset atrial fibrillation and migraine than controls without ASD. As novel findings, we found an increased risk for ischemic heart disease, AV conduction disorders, and ventricular fibrillation/tachycardia.Key messagesEven though patients have an excellent overall prognosis after percutaneous ASD closure, the increased incidence of major comorbidities like atrial fibrillation and heart failure prompts more thorough lifelong follow-up.This study's novel findings revealed the increased risk for ischemic heart disease, AV conduction disorders, or ventricular tachycardia/fibrillation during the follow-up.Major complications after the closure are rare; erosion is seen in 0.4% of the patients and embolization in 1.0% of the patients.

Cardiac positron emission tomography/computed tomography imaging accurately detects anatomically and functionally significant coronary artery disease.

BACKGROUND: Computed tomography (CT) is increasingly used to detect coronary artery disease, but the evaluation of stenoses is often uncertain. Perfusion imaging has an established role in detecting ischemia and guiding therapy. Hybrid positron emission tomography (PET)/CT allows combination angiography and perfusion imaging in short, quantitative, low-radiation-dose protocols. METHODS AND RESULTS: We enrolled 107 patients with an intermediate (30% to 70%) pretest likelihood of coronary artery disease. All patients underwent PET/CT (quantitative PET with (15)O-water and CT angiography), and the results were compared with the gold standard, invasive angiography, including measurement of fractional flow reserve when appropriate. Although PET and CT angiography alone both demonstrated 97% negative predictive value, CT angiography alone was suboptimal in assessing the severity of stenosis (positive predictive value, 81%). Perfusion imaging alone could not always separate microvascular disease from epicardial stenoses, but hybrid PET/CT significantly improved this accuracy to 98%. The radiation dose of the combined PET and CT protocols was 9.3 mSv (86 patients) with prospective triggering and 21.8 mSv (21 patients) with spiral CT. CONCLUSIONS: Cardiac hybrid PET/CT imaging allows accurate noninvasive detection of coronary artery disease in a symptomatic population. The method is feasible and can be performed routinely with <10 mSv in most patients. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00627172.

Low radiation dose imaging of myocardial perfusion and coronary angiography with a hybrid PET/CT scanner.

OBJECTIVES: To test the image quality and feasibility of a sequential low radiation dose protocol for hybrid cardiac PET/CT angiography (CTA). BACKGROUND: Multidetector computed tomography (MDCT) is a non-invasive method for coronary angiography. The negative predictive value of MDCT is high but perfusion imaging has a role in detecting functional significance of coronary lesions. This has encouraged combining these techniques. However, radiation dose is of concern. We report our first experiences with a low dose sequential CTA mode applicable to hybrid imaging. METHODS: In the first phase, 10 consecutive cardiac MDCT angiographies were performed with spiral acquisition and compared in terms of image quality and dose with the following 10 patients performed with a new sequential mode. In the second phase, feasibility and radiation dose of a combined (15)O-water rest-stress PET perfusion/sequential CTA protocol were assessed in another group of 61 consecutive patients. RESULTS: Mean effective radiation dose was 60% lower in the sequential group than in the spiral group (19.3 versus 7.6 mSv, P<0.001). In the second phase, the new sequential hybrid protocol proved possible in 87% of the patients given the preconditions determined by the manufacturer. Mean effective dose of the CT acquisition was 7.6 mSv and total dose from the PET/CTA hybrid study 9.5 mSv. CONCLUSION: Low dose PET/CT allows cardiac hybrid studies with <10 mSv. The protocol can be applied to almost nine out of 10 patients with CT image quality comparable to spiral acquisition.

Use of [11C]acetate and [15O]O2 PET for the assessment of myocardial oxygen utilization in patients with chronic myocardial infarction.

Carbon-11 acetate positron emission tomography (PET) has been widely used to assess regional oxidative metabolism of the heart. However, the accuracy of [11C]acetate PET in assessing oxidative metabolism in infarcted myocardium remains controversial. Thirteen patients with stable coronary artery disease and old myocardial infarction were studied. The 15O-based PET studies yielded regional blood flow (rMBF, ml/min/g) and oxygen consumption (rMMRO2, ml/min/g), which was compared with the myocardial clearance rate constant (kmono) of [11C]acetate in segments with rMBF > or = 75% (group A), 50%-74% (group B) or < 50% (group C) of the normal reference segment. Mean MBF was 0.96 +/- 0.08 ml/g/min in group A, 0.67 +/- 0.06 ml/g/min in group B and 0.42 +/- 0.07 ml/g/min in group C segments. The segmental rMMRO2 correlated linearly with kmono (r = 0.89, P < 0.001, y = 0.61x + 0.026). The kmono/rMMRO2 ratio was comparable in the group A and B segments (0.99 +/- 0.19 vs 1.07 +/- 0.21, P = NS). However, the ratio was significantly higher in the group C segments (1.28 +/- 0.35, P = 0.037). It is concluded that kmono of [11C]acetate correlates linearly with rMMRO2 determined by [15O]O2 inhalation. However, kmono appears to yield higher rMMRO2 estimates than the [15O]O2 method in low-flow areas.

Reduced myocardial carbon-11 hydroxyephedrine retention is associated with poor prognosis in chronic heart failure.

Abnormalities of the autonomic nervous system are known to be of prognostic significance in chronic heart failure (CHF). The prognostic value of positron emission tomography (PET) imaging of cardiac autonomic innervation in CHF has not been explored previously. We retrospectively studied the survival data of 46 NYHA class II-III CHF patients (mean LVEF 35% +/- 8%) who had undergone carbon-11 hydroxyephedrine (11C-HED) studies at the Turku PET Centre between August 1992 and March 1996. The origin of CHF was dilated cardiomyopathy in 13 of the 46 patients and coronary artery disease with at least one prior myocardial infarction in the remaining 33. Data on causes of death and heart transplantation were collected, and the statistically significant predictors of prognosis were analysed using Cox's proportional hazards regression. During the mean follow-up period of 55 +/- 19 months, 11 deaths occurred and two patients underwent heart transplantation successfully. Eleven end-points were classified as cardiac (nine sudden cardiac deaths and two deaths due to progressive heart failure) and two as non-cardiac. When divided into two groups based on the median of 11C-HED retention (mean 0.184 +/- 0.061, median 0.183), eight end-points (death or cardiac transplantation) were reached in the group with 11C-HED retention below the median and three in the group with 11C-HED retention above the median (P < 0.02). In proportional hazards regression analysis, only peak oxygen uptake (peak VO2), left ventricular end-diastolic volume and HED retention were found to be statistically significant. It is concluded that 11C-HED PET provides independent prognostic information in patients with CHF.

Myocardial efficiency during levosimendan infusion in congestive heart failure.

AIMS: Levosimendan, a novel calcium-dependent calcium sensitizer of the myocardial contractile proteins, also enhances diastolic relaxation and induces peripheral vasodilation by opening potassium channels. To assess the combined energetical effects of levosimendan infusion in vivo, we performed positron emission tomography in patients with decompensated chronic heart failure. METHODS AND RESULTS: Eight hospitalized patients with New York Heart Association functional class III or IV heart failure received levosimendan or placebo intravenously in a randomized double-blind cross-over study. During steady-state, dynamic positron emission tomography with [11C]acetate was used to assess myocardial oxygen consumption and [15O]H2O to measure myocardial blood flow. Cardiac performance and dimensions were assessed by pulmonary artery catheterization and echocardiography. Compared with healthy volunteers, myocardial oxygen consumption during placebo was elevated in the right ventricle but comparable in the left ventricle. During administration of levosimendan, cardiac output increased by 32% (P = .002) mainly because of higher stroke volume. Coronary, pulmonary, and systemic vascular resistance values were significantly reduced. Mean myocardial blood flow increased from 0.76 to 1.02 mL/min/g (P = .033). Levosimendan was neutral on myocardial oxygen consumption and left ventricular efficiency, but it improved right ventricular mechanical efficiency by 24% (P = .012). CONCLUSIONS: Levosimendan has an energetically favorable short-term profile in the treatment of congestive heart failure. It enhances cardiac output without oxygen wasting, particularly by improving efficiency in the right ventricle.

Cardiac positron emission tomography imaging with [11C]hydroxyephedrine, a specific tracer for sympathetic nerve endings, and its functional correlates in congestive heart failure.

The integrative mechanisms of autonomic dysfunction in congestive heart failure (CHF) remain poorly understood. We sought to study cardiac retention of [11C]hydroxyephedrine (HED), a specific tracer for sympathetic presynaptic innervation, and its functional correlates in CHF. Thirty patients with mild to moderate heart failure underwent resting cardiac HED positron emission tomography imaging, spectrum analysis testing of systolic pressure and heart rate variability in the resting supine and 70 degrees head-up tilt positions, and testing of baroreflex sensitivity. Compared with control subjects, global myocardial HED retention index was reduced by 30% (p <0.01) in patients with CHF. The HED retention index did not correlate significantly with heart rate variability. However, it correlated with baroreflex sensitivity at rest (r = 0.43, p = 0.05) and with systolic pressure low-frequency (0.03 to 0.15 Hz) variability at head-up tilt (r = 0.76, p <0.01), as well as with low-frequency systolic pressure variability response from baseline to tilt (r = 0.75, p <0.01). We conclude that cardiac HED retention is reduced in patients with CHF. This correlates with blunted vascular sympathetic effector responses during posture-induced reflex activation and baroreflex control of heart rate, suggesting an interdependence between cardiac presynaptic innervation abnormalities and neural mechanisms important to blood pressure maintenance in CHF.

Myocardial efficiency during calcium sensitization with levosimendan: a noninvasive study with positron emission tomography and echocardiography in healthy volunteers.

Dynamic positron emission tomography (PET) with [11C]acetate allows noninvasive assessment of myocardial oxygen consumption. In combination with echocardiography, PET enables determination of cardiac efficiency (defined as useful cardiac work per unit of oxygen consumption). We used this approach to compare the effects of levosimendan, a Ca(2+)-dependent calcium sensitizer, with dobutamine and sodium nitroprusside in healthy male volunteers. The effects of levosimendan on k(mono), an index of oxygen consumption, and cardiac efficiency were neutral, whereas the hemodynamic profile was consistent with balanced inotropism and vasodilatation. Dobutamine enhanced cardiac efficiency at the expense of increased oxygen requirement, but the effects of nitroprusside on k(mono) and cardiac efficiency were neutral. This study shows the feasibility of PET in phase 1 pharmacodynamic studies and suggests potential energetical advantages of calcium sensitization with levosimendan.

Listeria monocytogenes arthritis of several joints.

A patient with rheumatoid arthritis (RA) developed an infection caused by Listeria monocytogenes in her left knee and both shoulder joints. The clinical presentation of the disease was rather indolent with relatively moderate joint symptoms. Moreover, the synovial fluid sample was only slightly turbid with a white blood cell count of 23.5 x 10(9)/1. As compared to the earlier reported cases of L. monocytogenes septic arthritis, our patient is unique because she had infection in several joints. The polyarticular joint involvement combined with the clinical symptoms resembling the activation of RA posed us diagnostic difficulties.