Springer Science and Business Media LLC

Interpolation artifact is known to occur when the heart rate is decreased lower than the critical value for the specific pitch. The purpose of our study is to determine the minimum heart rate (minHR) for the specific pitch that provides images without interpolation artifact when using dual-source computed tomography (DSCT). We scanned the ‘thin slice thickness block’ of the CT performance phantom provided by the American Association of Physicists in Medicine using DSCT for variable pitches. Change in heart rate was simulated through ECG editing by changing R–R interval. Axial, sagittal, and coronal image sets were reconstructed and assessed for the presence and extent of interpolation artifact. MinHR at which no interpolation artifact was detected for each pitch value was determined. Length of interpolation artifact (LOA) on sagittal view was also measured when the heart rate was simulated at 10 bpm lower than the minHR on each pitch setting. MinHRs for each pitch value were 9–10 bpm from the estimated heart rate. However, minHR for the lowest pitch value 0.2, estimated heart value 40 bpm was 37 bpm. LOA was larger in the low heart rate condition. Measured values of minHR were correlated exactly with the calculated values. MinHRs that provide images without interpolation artifact for each pitch value when using DSCT were determined. The concept of minHR is important for obtaining high quality images of cardiac CT angiography when using DSCT.

Larger left atrial appendage (LAA) volume is associated with a higher risk of late recurrence (LR) in patients undergoing radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). However, it is unclear whether LAA volume predicts LR, independent of established risk factors. We sought to evaluate the value of LAA volume in predicting LR after RFCA for AF and to develop a score prediction model including LAA volume for these patients. We retrospectively studied 992 patients who underwent RFCA for AF and cardiac computed tomography before RFCA at a single center. At 3 years after RFCA, 362 patients (36.5 %) experienced recurrence. The multivariate Cox regression model showed that age ≥ 75 years (10 points), non-paroxysmal AF (9 points), diabetes mellitus (4 points), left atrial volume index (1 point per 10 ml/m2 rounded to the nearest integer), and the second (4.7 to < 7 ml/m2; 4 points) and third (≥ 7 ml/m2; 5 points) tertiles of the LAA volume index were independent risk factors LR. The above-mentioned risk factors were included in the integrated score model, and the C-index of the proposed score model was 0.715 (95 % confidence interval [CI] 0.679–0.752). LAA volume is an independent predictor of LR and the predictive model including LAA volume showed good discrimination power. These findings provide evidence for the inclusion of LAA volume in the risk stratification for AF recurrence in patients undergoing RFCA for AF.

To study the functional and metabolic correlates of left ventricular hypertrophy [LVH] in non-human primates, 7 hypertensive baboons [papio anubis] with 4.6 ± 0.1 years of hypertension produced by a two-kidney one-clip model, and echocardiographically documented concentric LVH underwent serial phosphorus-31 [P-31] NMR Spectroscopy studies at rest and during inotropic cardiac stress produced by dobutamine infusion [5 µg/kg/minute]. Responses in LVH baboons were compared to those in 5 normotensive, sex and weight-matched control animals. The ratio of P-31 NMR-S derived inorganic phosphates [Pi] to phosphocreatine [PCr] was significantly greater at rest in LVH baboons [0.53 ± 0.06 versus controls = 0.41 ± 0.17; P<0.05]. With dobutamine drug stress, the Pi/PCr ratio rose significantly in LVH baboons [0.77 ± 0.15 versus 0.56 ± 0.16; P<0.05 at 15 minutes]. Despite hemodynamic recovery, the 5 minute post-dobutamine Pi/PCr ratio remained elevated compared to baseline in LVH baboons only [0.78 ± 0.16 versus 0.53 ± 0.06; P<0.05]. In pre-instrumented baboons [n=5], the ‘transfer function’ of cardiac work [heart rate × LV end-systolic pressure × + dp/dt max] versus Pi/PCr ratio was abnormally shifted rightward and downward [r=0.80] with LVH as compared to the linearly increasing response in controls. We conclude thatin vivo P-31 NMR Spectroscopy studies during dobutamine stress demonstrate reduced PCr stores, delayed metabolic recovery following cessation of inotropic stress, and an abnormal rightward shift in the ‘transfer function’ in LVH baboons.

Conflicting data is present in the literature about patients who are treated with percutaneous coronary intervention (PCI) due to the exaggeration of the non culprit artery. The precise understanding of the non culprit artery in the setting of ST segment elevated myocardial infarct (STEMI) is important since the time and modality of the treatment is planned accordingly. The aim of this study is to evaluate the lesions in the non culprit coronary artery during primary PCI and control coronary angiography (CAG) using quantitative coronary angiography (QCA) in multivessel STEMI patients. In this study, multivessel disease STEMI patients whom underwent primary PCI between January 2010 and March 2011 were included. Critical stenosis degree was accepted as ≥70 % in the non culprit artery. All patients were evaluated with control CAG 1 month after primary PCI. Assessment with CAG was performed by two blinded cardiologists. QCA program was used to evaluate reference artery diameter (RAD), minimum luminal diameter (MLD) and degree of stenosis. With regard to the degree of stenosis, significant reduction was accepted as ≥15 % while % 5–15 decrease was accepted as moderate. Of the 81 patients, 61 were males and 20 were females (mean age 58.1 ± 10). In the control CAG, the degree of non culprit artery stenosis was found to be decreased (p < 0.001) while RAD and MLD were increased (p < 0.001 and p < 0.001 respectively). Significant decrease in critical non culprit artery lesions was detected in 22 patients (20.9 %) meanwhile moderate reduction was observed in 26 patients (24.7 %). In 14 patients (13.3 %), non culprit artery lesions accepted as critical during primary PCI were found to be non critical during the control CAG. Planned intervention was cancelled and medical treatment was initiated in those 14 patients. Our data indicated using QCA, approximately the half of non culprit lesions were found less critical during control CAG when compared to primary PCI. Therefore, it is concluded that complete revascularization during primary PCI should be avoided in multivessel STEMI patients and critical non culprit artery lesions should be re-evaluated with later control CAG.

Purpose: To evaluate coronary artery disease (CAD) patients regarding to their perfusion-glucose uptake relationship at rest for all myocardial regions and to determine whether this evaluation could typify patients with different positron emission tomography (PET)-pattern proportions and pathophysiological characteristics. Methods: Rest/dipyridamole H2 15O and 18FDG PET studies were performed in 23 patients with left ventricular dysfunction. Regional index (relative perfusion, %H2 15O; relative glucose uptake, %18FDG) allowed to detect perfusion-metabolism mismatch (i.e. hibernation) and dipyridamole-induced reversible stress defects (RSD). Results: The correlation (r) between %H2 15O and %18FDG at rest allowed definition of three groups: correlated (CORR; r > 0.7; n = 10), semicorrelated (SEMI; 0.5 < r ≤ 0.7; n = 6) and uncorrelated (UNCO; r ≤ 0.5; n = 7). In UNCO, 96% of regions had a %H2 15O ≥ 55% (p < 0.01 vs. 89 and 82% in SEMI and CORR) and 95% of regions had a %18FDG ≥ 55% (p < 0.01 vs. 78 and 71% in SEMI and CORR). Mismatch proportions increased from CORR to SEMI and UNCO (11, 19 and 27%; p < 0.02) and proportion of regions with RSD was higher in UNCO and SEMI (25 and 24 vs. 6% in CORR; p < 0.01). Proportion of mismatch with RSD was at least three fold higher in UNCO (17/58) (p < 0.01 vs. 3/33 and 1/16 in SEMI and CORR). Conclusions: Analysis of perfusion and glucose uptake at rest allowed to typify three categories of CAD patients with different PET-patterns proportions, distinctive ranges of perfusion and glucose uptake and distinctive hyperemic response. Our results suggest that myocardial hibernation associated with defective hyperemic response is specific of patients with preserved perfusion and glucose uptake.

Transient left ventricular apical ballooning syndrome (TLVABS) is an acute cardiac disease that is characterized by transient left ventricular systolic dysfunction involving the apical region. The symptoms and electrocardiographic changes of TLVABS mimic those observed in acute myocardial infarction while obstructive coronary arterial lesions are not seen in patients with TLVABS. TLVABS usually occurs in elderly women after physical or emotional stress. However, it is very rare in children and so it not well known to pediatricians. Accordingly, TLVABS in children can be misdiagnosed as myocarditis or cardiomyopathy. We report here on a case of child who showed the typical findings of TLVABS in association with pericarditis. He presented with dyspnea and pericardial effusion, which required pericardiocentesis. After pericardiocentesis, he showed the typical echocardiographic and electrocardiographic findings of TLVABS. The MRI findings at 14 days after the initial symptoms showed normal coronary arteries and normal left ventricular function without any wall motion abnormalities. In addition, no delayed hyper enhancement was found on delayed-enhanced (DE)-MRI. We also reviewed the other reported cases of TLVABS in patients who were under the age of 40.

Myocardial tissue is sensitive to insulin resistance (IR) due to its interactions with insulin levels. Previous studies demonstrated that heart failure prevalence was higher in IR patients. Evaluation of myocardial deformation by multilayer global longitudinal strain (MGLS) might provide more information about IR related left ventricular dysfunction. In this study, we aimed to investigate subclinical LV dysfunction with MGLS in patients with IR. The study was designed as a prospective cross-sectional study. The present study included 64 patients with IR (+), and 54 subjects without IR (−) prospectively. The homeostasis model of insulin resistance (HOMA-IR) was used to quantify insulin resistance. Specific analysis for endocardial, mid-myocardial and epicardial layers were performed by two-dimensional (2D) speckle tracking echocardiography (STE) for multilayer global longitudinal strain. MGLS (Endocard-Mid-myocard-Epicard) values were significantly lower in the IR (+) group compared to IR (−) group ((GLS-endocard; − 15.1 ± 1.5 vs. − 18.7 ± 1.3, p < 0.001), (GLS-mid-myocard; − 16.0 ± 2.0 vs. − 18.0 ± 2.0, p < 0.001), (GLS-epicard; − 17.0 ± 1.7 vs. − 18.01 ± 1.94, p = 0.004)). GLS-endocard levels were significantly and positively correlated with HOMA-IR levels (r = 0.643, p < 0.001). HOMA-IR and age were found to be independent factors in detecting a decrease in GLS-endocard level in regression analysis. In conclusion, our data reveal that IR (+) patients had significantly lower strain values compared to IR (−) group. Besides, we presented that the HOMA-IR value was an independent predictor of subclinical left ventricular dysfunction.

A young male who presented with atypical chest pain was found to have a primary cardiac tumor. Chest X-ray, electrocardiogram, and echocardiographic findings can be nonspecific. Differential diagnosis and the role of different diagnostic modalities including echocardiogram, computerized tomography and magnetic resonance imaging are discussed.