Aims Quantitative flow ratio (QFR) is a recently developed technique to calculate fractional flow reserve (FFR) based on 3D quantitative coronary angiography and computational fluid dynamics,... Show moreAims Quantitative flow ratio (QFR) is a recently developed technique to calculate fractional flow reserve (FFR) based on 3D quantitative coronary angiography and computational fluid dynamics, obviating the need for a pressure-wire and hyperaemia induction. QFR might be used to guide patient selection for FFR and subsequent percutaneous coronary intervention (PCI) referral in hospitals not capable to perform FFR and PCI. We aimed to investigate the feasibility to use QFR to appropriately select patients for FFR referral.Methods and results Patients who underwent invasive coronary angiography in a hospital where FFR and PCI could not be performed and were referred to our hospital for invasive FFR measurement, were included. Angiogram images from the referring hospitals were retrospectively collected for QFR analysis. Based on QFR cut-off values of 0.77 and 0.86, our patient cohort was reclassified to 'no referral' (QFR >= 0.86), referral for 'FFR' (QFR 0.78-0.85), or 'direct PCI' (QFR <= 0.77). In total, 290 patients were included. Overall accuracy of QFR to detect an invasive FFR of <= 0.80 was 86%. Based on a QFR cut-off value of 0.86, a 50% reduction in patient referral for FFR could be obtained, while only 5% of these patients had an invasive FFR of <= 0.80 (thus, these patients were incorrectly reclassified to the 'no referral' group). Furthermore, 22% of the patients that still need to be referred could undergo direct PCI, based on a QFR cut-off value of 0.77.Conclusion QFR is feasible to use for the selection of patients for FFR referral. Show less
Left ventricular (LV) diastolic dysfunction and increased arterial stiffness are common in patients with diabetes mellitus (DM). However, the relation between these two pathophysiological factors... Show moreLeft ventricular (LV) diastolic dysfunction and increased arterial stiffness are common in patients with diabetes mellitus (DM). However, the relation between these two pathophysiological factors remains unclear. The aim of this study was to investigate the relationship between LV diastolic function and arterial stiffness as assessed with applanation tonometry. In 142 asymptomatic patients with DM (mean age 48 years, 75 (53 %) men, 72 (51 %) patients with type 2 DM) LV diastolic function was assessed with echocardiography. Arterial stiffness was evaluated measuring the aortic pulse wave velocity (PWV) whereas wave reflection was assessed measuring central systolic blood pressure (cSBP), central pulse pressure (cPP), and augmentation index (AIx) with applanation tonometry. Mean E/A ratio, E' and E/E' ratio were 1.1 ± 0.3, 8.1 ± 2.3 and 9.2 ± 3.3 cm/s, respectively. Mean PWV, mean cSBP, median cPP and mean AIx were 7.9 ± 2.4 m/s, 122 ± 17 mmHg, 40 [35-51] mmHg and 17.9 ± 12.1 %, respectively. PWV was independently associated with LV diastolic dysfunction grade (β = 0.76, p = 0.03). In contrast, measures of wave reflection, cPP, cSBP and AIx were independently related with E/A ratio, but not with the LV diastolic dysfunction grade. Parameters of arterial stiffness and wave reflection are associated with echocardiographic indices of LV diastolic function in asymptomatic patients with DM. Therapies that prevent progression of arterial stiffness and reduce late-systolic pressure overload may help to reduce the prevalence of LV diastolic dysfunction in this population. Show less
Scherptong, R.W.C.; Vliegen, H.W.; Wall, E.E. van der; Hilhorst-Hofstee, Y.; Bax, J.J.; Scholte, A.J.; Delgado, V. 2011
Background-Left ventricular (LV) torsion is emerging as a sensitive parameter of LV systolic myocardial performance. The aim of the present study was to explore the effects of acute myocardial... Show moreBackground-Left ventricular (LV) torsion is emerging as a sensitive parameter of LV systolic myocardial performance. The aim of the present study was to explore the effects of acute myocardial infarction (AMI) on LV torsion and to determine the value of LV torsion early after AMI in predicting LV remodeling at 6-month follow-up. Methods and Results-A total of 120 patients with a first ST-segment elevation AMI (mean +/- SD age, 59 +/- 10 years; 73% male) were included. All patients underwent primary percutaneous coronary intervention. After 48 hours, speckle-tracking echocardiography was performed to assess LV torsion; infarct size was assessed by myocardial contrast echocardiography. At 6-month follow-up, LV volumes and LV ejection fraction were reassessed to identity patients with LV remodeling (defined as a >= 15% increase in LV end-systolic volume). Compared with control subjects, peak LV torsion in AMI patients was significantly impaired (1.54 +/- 0.64 degrees/cm vs 2.07 +/- 0.27 degrees/cm, P < 0.001). By multivariate analysis, only LV ejection fraction (beta = 0.36, P < 0.001) and infarct size (beta = -0.47, P < 0.001) were independently associated with peak LV torsion. At 6-month follow-up, 19 patients showed LV remodeling. By multivariate analysis, only peak LV torsion (odds ratio = 0.77; 95% CI, 0.65-0.92; P = 0.003) and infarct size (odds ratio = 1.04; 95% CI, 1.01-1.07; P = 0.021) were independently related to LV remodeling. Peak LV torsion provided modest but significant incremental value over clinical, echocardiographic, and myocardial contrast echocardiography variables in predicting LV remodeling. By receiver-operating characteristics curve analysis, peak LV torsion <= 1.44 degrees/cm provided the highest sensitivity (95%) and specificity (77%) to predict LV remodeling. Conclusions-LV torsion is significantly impaired early after AMI. The amount of impairment of LV torsion predicts LV remodeling at 6-month follow-up. (Circ Cardiovasc Imaging. 2010; 3: 433-442.) Show less
The impact of left ventricular (LV) dyssynchrony after acute myocardial infarction (AMI) on LV ejection fraction (EF) is unknown. One hundred twenty-nine patients with a first ST-elevation AMI (58 ... Show moreThe impact of left ventricular (LV) dyssynchrony after acute myocardial infarction (AMI) on LV ejection fraction (EF) is unknown. One hundred twenty-nine patients with a first ST-elevation AMI (58 +/- 11 years, 78% men) and QRS duration <120 ms were included. All patients underwent primary percutaneous coronary intervention. Real-time 3-dimensional echocardiography and myocardial contrast echocardiography were performed to assess LV function, LV dyssynchrony, and infarct size. LV dyssynchrony was defined as the SD of the time to reach the minimum systolic volume for 16 LV segments, expressed in percent cardiac cycle (systolic dyssynchrony index [SDI]). Myocardial perfusion at myocardial contrast echocardiography was scored (1 = normal/homogenous; 2 = decreased/patchy; 3 = minimal/absent) using a 16-segment model; a myocardial perfusion index, expressing infarct size, was derived by summing segmental contrast scores and dividing by the number of segments. SDI in patients with AM! was 5.24 +/- 2.23% compared to 2.02 +/- 0.70% of controls (p <0.001). Patients with AMI and LVEF <45% had significantly higher SDI compared to patients with LVEF >= 45% (4.29 +/- 1.44 vs 6.95 +/- 2.40, p <0.001). At multivariate analysis, SDI was independently related to LVEF; in addition, the impact of SDI on LV systolic function was incremental to infarct size and anterior location of AM! (F change 16.9, p <0.001). In conclusion, LV synchronicity is significantly impaired soon after AMI. LV dyssynchrony is related to LVEF and has an additional detrimental effect on LV function, beyond infarct size and the anterior location of AMI. (C) 2010 Elsevier Inc. All rights reserved. (Am J Cardiol 2010;105:306-311) Show less
