Simultaneous assessment of left ventricular mechanical dyssynchrony using integrated 13N-ammonia PETMR system: direct comparison of PET phase analysis and MR feature tracking.

BACKGROUND: To compare phase analysis with positron emission tomography (PA) and magnetic resonance feature tracking derived myocardial strain (FT) for left ventricular (LV) mechanical dyssynchrony using PETMR system in patients with ischemic heart disease. METHODS AND RESULTS: Patients who underwent rest-pharmacological stress 13N ammonia PETMR were enrolled. Histogram bandwidth (BW) and phase standard deviation (PSD) were compared to global longitudinal, long axis radial, short axis circumferential, and radial strain (GLS, GRS, SA Circ, and SA Rad) obtained from FT. LV dyssynchrony index (SDI) derived from PA and FT were compared. BW and PSD showed significant correlations with FT (a Pearson's coefficient r = 0.64, P < .0001, and r = 0.51, P < .0001 for SA Circ; r = 0.67, P < .0001, and r = 0.74, P < .0001 for GLS; r = - 0.60, P < .0001, r = - 0.61, P < .0001 for SA Rad; r = - 0.62, P < .0001, and r = - 0.68, P < .0001 for GRS, respectively). Bland-Altman plots for SDI showed a preferable agreement (95% limit of agreement - 0.12 to 0.075, - 0.20 to 0.098, - 0.38 to 0.077, and - 0.37 to 0.032; bias 0.0068 ± 0.056, 0.026 ± 0.068, 0.11 ± 0.088, and 0.13 ± 0.079 for SA Circ, SA Rad, GLS, and GRS, respectively). CONCLUSION: In simultaneous acquisition using PETMR, comparison of PET phase analysis and MR strain showed a good correlation.

Change of Exhaled Acetone Concentration Levels in Patients with Acute Decompensated Heart Failure.

Exhaled acetone concentration is one of the expected compounds to be a breath biomarker in heart failure. However, it has not been clarified how exhaled acetone concentration changes in clinical course of heart failure.To investigate whether exhaled acetone concentration changes after treatment in acute decompensated heart failure (ADHF).This study included 19 patients with ADHF (ADHF group) and eight patients with stable heart failure (control group). Exhaled acetone was collected from these patients, and the concentration was measured with gas chromatography.The ADHF group had higher heart rates (P = 0.046), higher New York Heart Association class (P < 0.001), higher levels of brain natriuretic peptide (P = 0.026), blood total ketone bodies (P = 0.015), and exhaled acetone concentration (P < 0.001), compared with the control group. In ADHF group, exhaled acetone concentration significantly decreased after treatment (median: 2.40 versus 0.92 ppm, P < 0.001). However, in the control group, exhaled acetone concentration did not significantly change (median: 0.73 versus 0.49 ppm, P = 0.141).In these preliminary findings, exhaled acetone concentration in patients with ADHF drastically decreased by treatment. Serial exhaled acetone measurement might be useful to evaluate the course of ADHF.

Optimal noninvasive assessment of diastolic heart failure in patients with atrial fibrillation: comparison of tissue doppler echocardiography, left atrium size, and brain natriuretic peptide.

OBJECTIVE: The aim of this study was to evaluate whether the ratio of early diastolic transmitral velocity to early diastolic mitral annular velocity (E/E') can be applied to identify diastolic heart failure (HF) noninvasively rather than using brain natriuretic peptide (BNP) or enlargement of left atrium (LA) in patients with atrial fibrillation (AF) by comparing the severity of HF symptoms. Moreover, we investigated the relationship between the changes in E/E' and the severity of HF or LA remodeling in the follow-up period. METHODS: We examined 73 patients with nonvalvular AF disease and preserved left ventricular ejection fraction (>50%), ie, patients with diastolic HF accompanied with New York Heart Association (NYHA) functional class I to IV (n = 32, HF group) and those without HF (n = 41, non-HF group). No patients showed dyspnea caused by anemia, renal failure, lung disease, or other disease states except HF. We evaluated E, E', and E/E' by Doppler echocardiography, and the LA area (LAA) by 2-dimensional echocardiography. BNP levels were also examined. A follow-up study was performed in 18 of the 32 patients with HF. RESULTS: E/E', LAA, and BNP were higher in the HF group than in the non-HF group (E/E', 15 +/- 5 vs 9 +/- 2; LAA, 24 +/- 6 vs 20 +/- 6 cm(2); and BNP, 321 +/- 200 vs 140 +/- 76 pg/mL, each P < .01). Using the receiver operating characteristic curve for identification of symptomatic diastolic HF with NYHA functional class II to IV, the areas under the curves were: E/E', 0.96 (95% confidence interval 0.91-1.0); LAA, 0.77 (95% confidence interval 0.64-0.89); and BNP, 0.85 (95% confidence interval 0.75-0.95). In the HF group, 18 patients who were re-examined 17 +/- 9 weeks after were divided into two groups, depending on the improvement in NYHA functional class, ie, improved group (n = 10) and unchanged group (n = 8). In the follow-up period, E (112 +/- 20-94 +/- 21 cm/s), E/E' (17.1 +/- 5-13.1 +/- 3), and LAA (28 +/- 5-24 +/- 4) decreased in the improved group (each P < .05), but E' and BNP did not. CONCLUSIONS: E/E' could be useful in identifying symptomatic diastolic HF and evaluating the functional state in the process of HF in patients with AF. Moreover, E/E' is able to assess the improvement of diastolic HF in AF.