[Show abstract][Hide abstract] ABSTRACT: Rationale:
Chronic obstructive pulmonary disease patients develop increased cardiovascular morbidity with structural alterations.
This double-blind, placebo-controlled, crossover study investigated the effect of lung deflation on cardiovascular structure and function using cardiac magnetic resonance.
Forty-five hyperinflated chronic obstructive pulmonary disease patients were randomised (1:1) to 7 (maximum 14) days inhaled corticosteroid/long-acting β2-agonist fluticasone furoate/vilanterol 100/25 μg or placebo (7-day minimum washout).
change from baseline in right ventricular end diastolic volume index versus placebo.
Measurements and main results:
There was a 5.8 ml/m2 (95% confidence interval 2.74-8.91; P < 0.001) increase in change from baseline right ventricular end-diastolic volume index and a 429 ml (P < 0.001) reduction in residual volume with fluticasone furoate/vilanterol versus placebo. Left ventricular end-diastolic and left atrial end-systolic volumes increased by 3.63 ml/m2 (P = 0.002) and 2.33 ml/m2 (P = 0.002). In post-hoc analysis, right ventricular stroke volume increased by 4.87 ml/m2 (P = 0.003); right ventricular ejection fraction was unchanged. Left ventricular adaptation was similar; left atrial ejection fraction improved by +3.17% (P < 0.001). Intrinsic myocardial function was unchanged. Pulmonary artery pulsatility increased in two of three locations (main +2.9%, P = 0.001; left +2.67%, P = 0.030). Fluticasone furoate/vilanterol safety profile was similar to placebo.
Pharmacological treatment of chronic obstructive pulmonary disease has consistent beneficial and plausible effects on cardiac function and pulmonary vasculature that may contribute to favorable effects of inhaled therapies. Future studies should investigate the effect of prolonged lung deflation on intrinsic myocardial function. Clinical trial registration available at www.clinicaltrials.gov, ID NCT01691885.
No preview · Article · Nov 2015 · American Journal of Respiratory and Critical Care Medicine
[Show abstract][Hide abstract] ABSTRACT: Objective: Hypertension remains a major cause of cardiovascular morbidity and mortality worldwide. Persistent blood pressure (BP) elevation may lead to left ventricular (LV) hypertrophy and heart failure. We wanted to assess the impact of high BP on LV function in an asymptomatic cohort, with no evidence of LV hypertrophy. Design and method: We included all 96 asymptomatic volunteers scanned with cardiovascular magnetic resonance (CMR) as part of the HAPPY London primary prevention study. BP was taken sitting, from the left arm with at least 2 consistent measures. We compared those with elevated clinic BP (systolic >140mmHg and/or diastolic >90mmHg) to those with a 'normal' BP, regardless of whether on BP treatment. CMR at 1.5 Tesla was performed within 2 weeks of the clinic. Results: Average age was 64.5 years and 74% were males, similar in both groups. Half were taking antihypertensive medication in both groups. 31 participants had elevated clinic BP and the remaining 65 had normal BP. Mean BPs were: 150mmHg +/- 8 / 86mmHg +/- 11 in high BP group and 127mmHg +/- 8 / 77mmHg +/- 7 in the normal (Table 1). Copyright
No preview · Article · Jun 2015 · Journal of Hypertension
[Show abstract][Hide abstract] ABSTRACT: An updated version of the European Association of Cardiovascular Imaging (EACVI) Core Syllabus for the European Cardiovascular Magnetic Resonance (CMR) Certification Exam is now available online. The syllabus lists key elements of knowledge in CMR. It represents a framework for the development of training curricula and provides expected knowledge-based learning outcomes to the CMR trainees, in particular those intending to demonstrate CMR knowledge in the European CMR exam, a core requirement in the CMR certification process.
Preview · Article · May 2014 · European Heart Journal – Cardiovascular Imaging
[Show abstract][Hide abstract] ABSTRACT: Restoration of sinus rhythm may result in an improvement of left heart function in patients with atrial fibrillation (AF). Cardiovascular magnetic resonance (CMR) feature tracking (FT) technique may help detect subtle wall-motion abnormalities. Consequently this study aimed to analyse existence and reversibility of subclinical cardiac dysfunction following atrial fibrillation ablation. 28 consecutive patients (mean age 61 years) with paroxysmal AF underwent pulmonary vein isolation. CMR imaging was done 3 (±3) days before and 3.4 (±1.1) months after ablation. Left heart function was determined by performing FT analysis. Statistical analysis included paired student's t test, random effects metaanalysis to assess the cohort's health status and Bland-Altman analysis. 17 patients (61 %) were free from AF at follow-up. Bland-Altman analysis showed good coefficients of variation. Of all 195 parameters, 27 changed (14 %):9 improved significantly (5 %), 12 worsened significantly (6 %), whereas 6 parameters worsened not significantly (3 %). 18 of 120 systolic parameters changed (15 %), 14 worsened (12 %), 4 improved (3 %). In 9 of 75 diastolic parameters, values changed (12 %): 5 improved (7 %) and 4 worsened (5 %). Meta-analysis revealed that our collective's FT values at baseline didn't differ significantly from healthy volunteers' values [Q values of 0.01 (p value 0.921) and 1.499 (p value 0.221)]. AF patients undergoing ablation appear to have near normal cardiac wall motion, which does not improve following successful ablation. Feature tracking analysis is a reliable tool to determine treatment effects but is more likely to show positive findings if the population is unhealthy.
No preview · Article · Sep 2013 · The international journal of cardiovascular imaging
[Show abstract][Hide abstract] ABSTRACT: Background: Apical hypertrophic cardiomyopathy (HCM) is commonly associated with drug-refractory chest pain. We sought to determine whether, in apical HCM, coronary perfusion time is abbreviated by the diastolic persistence of apical contraction, resulting in impaired myocardial perfusion and chest pain.
Methods: 62 apical HCM patients had cardiac magnetic resonance (CMR) scans assessed for stress perfusion (myocardial perfusion reserve index (MPRi)), late gadolinium enhancement (LGE; % of myocardial volume) left ventricular (LV) volumes and LV contractile persistence (% total cardiac cycle) at the LV apex and base. Radial and circumferential strain were assessed. Patients were divided into three groups on the basis of severity of contractile persistence. The interval between earliest and latest systolic peaks was measured from strain data from each of the apical segments.
Results: Compared to subjects with the least contractile persistence (C1), those with the most (C3) were more likely to have chest pain (94% vs 63%, p<0.05) and lower MPRi (0.90±0.24 vs 1.43±0.50, p<0.05). Multiple regression analyses included contractile persistence, LVH, %LGE, age and gender. Contractile persistence was independently associated with chest pain (0.4 per 10% cardiac cycle, CI 95%; 0.1 to 0.8, p<0.05) and a reduction in apical MPRi (-0.09 per 10% cardiac cycle, CI 95%; -0.04 to -0.15, p<0.01). There were striking differences in systolic strain between C1 and C3. First, radial strain was almost absent in C3, with only post-systolic contraction detected. Second, temporal dispersion in circumferential strain was greater in C3 than C1 (230±101ms vs 114±44ms, p<0.05). Using the convention >130ms as a threshold, circumferential dyssynchrony was present in 25% of C1 and 81% of C3 patients (p<0.001) and radial dyssynchrony in 65% of C1 and 95% of C3 patients (p<0.05). In patients with radial dyssynchrony, the earliest peak was most often in the inferior or anterior segments (60%) and the latest in the lateral segment (33%). In patients with circumferential dyssynchrony, the earliest peak was most often in the inferior or anterior segments (59%) and the latest in the lateral segment (41%).
Conclusion: In apical HCM, regional persistence of contractility into diastole causes myocardial ischaemia and chest pain. This is the first description of contractile persistence and dyssynchrony as a mechanism for myocardial perfusion abnormalities and presents novel therapeutic opportunities for drug-refractory chest pain in apical HCM.
Preview · Article · Aug 2013 · European Heart Journal
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: For late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) assessment of atrial scar to guide management and targeting of ablation in AF, an objective, reproducible method of identifying atrial scar is required. Objective: We describe an automated method for operator-independent quantification of LGE that correlates with co-located endocardial voltage and clinical outcomes. METHODS: LGE CMR imaging was performed at 2 centres, before and 3 months after pulmonary vein isolation (PVI) for paroxysmal AF (PAF) (N=50). Left atrial (LA) surface scar map was constructed using automated software, expressing intensity as multiples of standard deviation (SD) above blood pool mean. 21 patients underwent endocardial voltage mapping at the time of PVI (11 were redo procedures). Scar maps and voltage maps were spatially registered to the same MRA segmentation. RESULTS: LGE levels of 3, 4 and 5 SD above blood pool intensity were associated with progressively lower bipolar voltages compared to the preceding enhancement level (0.85± 0.33mV, 0.50± 0.22mV and 0.38 ±0.28mV, p=0.002, p<0.001 and p=0.048 respectively).The proportion of atrial surface area classified as scar (i.e. >3 SD above blood pool mean) on pre-ablation scans was greater in patients with post-ablation AF recurrence than those without recurrence (6.6 ± 6.7% vs 3.5 ± 3.0%, p =0.032). LA volume >102ml was associated with a significantly greater proportion of LA scar (6.4± 5.9 vs 3.4± 2.2%, p=0.007). CONCLUSION: Left atrial scar quantified automatically by a simple objective method correlates with co-located endocardial voltage. Greater pre-ablation scar is associated with LA dilatation and AF recurrence.
Full-text · Article · May 2013 · Heart rhythm: the official journal of the Heart Rhythm Society
[Show abstract][Hide abstract] ABSTRACT: Introduction:
We tested the hypothesis that cardiovascular magnetic resonance (CMR) imaging can reliably distinguish the presence or absence of left atrial (LA) ablation lesions by blinded analysis of pre- and postablation imaging.
Consecutive patients at 2 centers undergoing pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation by either wide area circumferential radiofrequency ablation (WACA) or ostial ablation with a cryoballoon underwent CMR late gadolinium enhancement (LGE) imaging pre- and 3 months postablation. Imaging was anonymized for blinded analysis of (1) LGE images, and (2) a 3D fusion image with LGE projected onto a segmented LA surface. Scans were categorized using both assessment techniques separately as pre- or postablation, and if postablation, whether lesions were in an ostial or WACA distribution.
LGE imaging was performed in 50 patients (aged 60 ± 10 years, 68% male, 24 underwent WACA and 26 had cryoablation). Sensitivity and specificity for detection of ablation lesions was 60% and 96% on LGE imaging. Sensitivity was higher using 3D fusion imaging (88%; P = 0.003). The proportion in whom lesions were both detected and the distribution correctly assessed as WACA or ostial was higher with 3D fusion imaging compared to LGE imaging (54% vs 28%; P = 0.014). There was no difference in the detection of radiofrequency ablation lesions compared to cryoablation lesions (58% vs 62%; P = 1.000).
LGE imaging of atrial scar is not yet sufficiently accurate to reliably identify ablation lesions or to determine lesion distribution.
No preview · Article · Nov 2012 · Journal of Cardiovascular Electrophysiology
[Show abstract][Hide abstract] ABSTRACT: Objective:
The objective of this study was to demonstrate soft palate MRI at 1.5 and 3 T with high temporal resolution on clinical scanners.
Six volunteers were imaged while speaking, using both four real-time steady-state free-precession (SSFP) sequences at 3 T and four balanced SSFP (bSSFP) at 1.5 T. Temporal resolution was 9-20 frames s(-1) (fps), spatial resolution 1.6 × 1.6 × 10.0-2.7 × 2.7 × 10.0 mm(3). Simultaneous audio was recorded. Signal-to-noise ratio (SNR), palate thickness and image quality score (1-4, non-diagnostic-excellent) were evaluated.
SNR was higher at 3 T than 1.5 T in the relaxed palate (nasal breathing position) and reduced in the elevated palate at 3 T, but not 1.5 T. Image quality was not significantly different between field strengths or sequences (p=NS). At 3 T, 40% acquisitions scored 2 and 56% scored 3. Most 1.5 T acquisitions scored 1 (19%) or 4 (46%). Image quality was more dependent on subject or field than sequence. SNR in static images was highest with 1.9 × 1.9 × 10.0 mm(3) resolution (10 fps) and measured palate thickness was similar (p=NS) to that at the highest resolution (1.6 × 1.6 × 10.0 mm(3)). SNR in intensity-time plots through the soft palate was highest with 2.7 × 2.7 × 10.0 mm(3) resolution (20 fps).
At 3 T, SSFP images are of a reliable quality, but 1.5 T bSSFP images are often better. For geometric measurements, temporal should be traded for spatial resolution (1.9 × 1.9 × 10.0 mm(3), 10 fps). For assessment of motion, temporal should be prioritised over spatial resolution (2.7 × 2.7 × 10.0 mm(3), 20 fps). Advances in knowledge Diagnostic quality real-time soft palate MRI is possible using clinical scanners and optimised protocols have been developed. 3 T SSFP imaging is reliable, but 1.5 T bSSFP often produces better images.
Preview · Article · Jul 2012 · The British journal of radiology