Use of delayed-enhancement magnetic resonance imaging for fibrosis detection in the atria: a review.

This paper presents a review of the different approaches existing in the literature to detect and quantify fibrosis in contrast-enhanced magnetic resonance images of the left atrial wall. The paper provides a critical analysis of the different methods, stating their advantages and limitations, and providing detailed analysis on the possible sources of variability in the final amount of detected fibrosis coming from the use of different techniques.

Cardiac memory in cardiac resynchronization therapy: A vectorcardiographic comparison of biventricular and left ventricular pacing.

INTRODUCTION: "Cardiac memory" (CM) refers to a change in repolarization induced by an altered pathway of activation, manifested after resumption of spontaneous ventricular activation (SVA). AIMS: To investigate for the first time in humans the effects of left ventricular (LV) pacing on CM development through vectorcardiography (VCG). METHODS: We studied 28 patients with heart failure (HF) and left bundle branch block (LBBB) treated with cardiac resynchronization therapy (CRT). Fourteen patients underwent biventricular (BIV) stimulation; the other 14 underwent LV stimulation only. VCG was acquired during SVA at baseline and during AAI and DDD pacing immediately after and 7 and 90 days after the implant. RESULTS: At baseline, in both groups, the QRS and T vectors angles were those specific of LBBB pattern. During DDD pacing, QRS vector angle changed to the right and upward in BIV patients while no significant differences were observed in LV patients. During AAI pacing, T vector angle changed significantly in BIV patients, following the direction of the paced QRS and amplitude significantly increased. In LV patients no significant differences in T vector angles were observed. Only T vector amplitude significantly increased at 7 days (p=0.03) and at 90 days (p=0.008 vs baseline). CONCLUSION: In patients with LBBB, BIV pacing induces cardiac memory development as a significant change in T vector magnitude and angle, while LV pacing doesn't induce significant modifications in QRS and T vector angles and CM is manifested only as a significant T vector amplitude change.

The Value of a Coronary Computed Tomography Angiography plus Stress Cardiac Magnetic Resonance Imaging Strategy for the Evaluation of Patients with Chronic Coronary Syndrome.

Background: Noninvasive imaging methods, either anatomical or functional tests, serve as essential instruments for the appropriate management of patients with established or suspected coronary artery disease (CAD). We sought to evaluate the safety and efficacy of a coronary computed tomography angiography (CCTA) plus stress cardiac magnetic resonance imaging (S-CMR) strategy in patients with chronic coronary syndrome (CCS). Methods: Patients with suspected CCS showing intermediate coronary plaques (stenosis 30-70%) at CCTA underwent S-CMR. Patients with a positive S-CMR were referred to invasive coronary angiography (ICA) plus instantaneous wave-free ratio (iFR), and myocardial revascularization if recommended. All patients received guideline-directed medical therapy (GDMT), including high-dose statins, regardless of myocardial revascularization. The primary endpoint was a composite of death from cardiovascular causes, non-fatal myocardial infarction, and unplanned revascularization. Results: According to the results of CCTA, 62 patients showing intermediate coronary plaques underwent S-CMR, which was positive for a myocardial perfusion deficit in n = 17 (27%) and negative in n = 45 (73%) patients. According to the results of ICA plus iFR, revascularization was performed in 13 patients. No differences in the primary endpoint between the positive and negative S-CMR groups were observed at 1 year (1 [5.9%] vs. 1 [2.2%], p = 0.485) and after a median of 33.4 months (2 [11.8%] vs. 3 [6.7%]; p = 0.605). Conclusions: Our study suggests that a CCTA plus S-CMR strategy is effective for the evaluation of patients with suspicion of CCS at low-intermediate risk, and it may help to refine the selection of patients with intermediate coronary plaques at CCTA needing coronary revascularization.

Comparison of myocardial reperfusion between intracoronary versus intravenous cangrelor administration in patients undergoing primary percutaneous coronary intervention.

BACKGROUND: Myocardial reperfusion is the main target of treatment in patients with ST-segment elevation myocardial infarction (STEMI). The intracoronary administration of cangrelor bolus could favor a higher local drug concentration, favoring an earlier thrombotic resolution and a reduced distal micro-embolization. METHODS: Seventy-one patients undergoing primary percutaneous coronary intervention (PCI) for STEMI: 37 treated with intracoronary and 34 with intravenous bolus administration of cangrelor. The primary endpoint was ST-segment elevation resolution (STR) ≥ 50% after 30 min from the end of the PCI. Other explorative reperfusion indices investigated were: STR ≥ 50% at 24 hours, STR ≥ 70% at 30 min, Thrombolysis In Myocardial Infarction frame count and the QT dispersion. Moreover, acute and subacute stent thrombosis, bleeding events and 30-day mortality have been evaluated. RESULTS: More frequent STR ≥ 50% was observed in the intravenous cangrelor bolus group as compared to the intracoronary administration at 30 min (71.9% vs. 45.5%; p = 0.033), the difference was maintained 24 hours after PCI (87.1% vs. 63.6%; p = 0.030). STR ≥ 70% at 30 min was statistically more frequent in the intravenous bolus administration cohort (66.7% vs. 28.6% p = 0.02). At multivariable analysis, intravenous cangrelor administration was significantly related to STR ≥ 50% (odds ratio: 3.586; 95% confidence interval: 1.134-11.335; p = 0.030). The incidence of Bleeding Academic Research Consortium 3-5 bleedings was 15.5% and mortality was 4.2% without any significant difference between the two groups. CONCLUSIONS: In conclusion the results of the study do not show any advantages in the administration of intracoronary bolus of cangrelor in patients affected by STEMI and treated with primary PCI.

Application of the Seattle Heart Failure Model in patients on cardiac resynchronization therapy.

BACKGROUND: The Seattle Heart Failure Model (SHFM) is a multimarker risk assessment tool able to predict outcome in heart failure (HF) patients. AIM: To assess whether the SHFM can be used to risk-stratify HF patients who underwent cardiac resynchronization therapy with (CRT-D) or without (CRT) an implantable defibrillator. METHODS AND RESULTS: The SHFM was applied to 342 New York Heart Association class III-IV patients who received a CRT (23%) or CRT-D (77%) device. Discrimination and calibration of SHFM were evaluated through c-statistics and Hosmer-Lemeshow (H-L) goodness-of-fit test. Primary endpoint was a composite of death from any cause/cardiac transplantation. During a median follow-up of 24 months (25th-75th percentile [pct]: 12-37 months), 78 of 342 (22.8%) patients died; seven patients underwent urgent transplantation. Median SHFM score for patients with endpoint was 5.8 years (25th-75th pct: 4.25-8.7 years) versus 8.9 years (25th-75th pct: 6.6-11.8 years) for those without (P < 0.001). Discrimination of SHFM was adequate for the endpoint (c-statistic always ranged around 0.7). The SHFM was a good fit of death from any cause/cardiac transplantation, without significant differences between observed and SHFM-predicted survival. CONCLUSION: The SHFM successfully stratifies HF patients on CRT/CRT-D and can be reliably applied to help clinicians in predicting survival in this clinical setting.

Chronic total occlusion revascularization: A complex piece to "complete" the puzzle.

Treatment of coronary chronic total occlusion (CTO) with percutaneous coronary intervention (PCI) has rapidly increased during the past decades. Different strategies and approach were developed in the recent past years leading to an increase in CTO-PCI procedural success. The goal to achieve an extended revascularization with a high rate of completeness is now supported by strong scientific evidences and consequently, has led to an exponential increase in the number of CTO-PCI procedures, even if are still underutilized. It has been widely demonstrated that complete coronary revascularization, achieved by either coronary artery bypass graft or PCI, is associated with prognostic improvement, in terms of increased survival and reduction of major adverse cardiovascular events. The application of "contemporary" strategies aimed to obtain a state-of-the-art revascularization by PCI allows to achieve long-term clinical benefit, even in high-risk patients or complex coronary anatomy with CTO. The increasing success of CTO-PCI, allowing a complete or reasonable incomplete coronary revascularization, is enabling to overcome the last great challenge of interventional cardiology, adding a "complex" piece to "complete" the puzzle.

Wave Reflection and Ventriculo-Arterial Coupling in Bicuspid Aortic Valve Patients With Repaired Aortic Coarctation.

BACKGROUND: Ventriculo-arterial (VA) coupling in bicuspid aortic valve (BAV) patients can be affected by the global aortopathy characterizing BAV disease and the presence of concomitant congenital lesions such as aortic coarctation (COA). This study aimed to isolate the COA variable and use cardiovascular magnetic resonance (CMR) imaging to perform wave intensity analysis non-invasively to shed light on VA coupling changes in BAV. The primary hypothesis was that BAV patients with COA exhibit unfavorable VA coupling, and the secondary hypothesis was that BAV patients with COA exhibit increased wave speed as a marker of reduced aortic distensibility despite successful surgical correction. METHODS: Patients were retrospectively identified from a CMR database and divided into two groups: isolated BAV and BAV associated with repaired COA. Aortic and ventricular dimensions, global longitudinal strain (GLS), and ascending aortic flow data and area were collected and used to derive wave intensity from CMR data. The main variables for the analysis included all wave magnitudes (forward compression/expansion waves, FCW and FEW, respectively, and reflected backward compression wave, BCW) and wave speed. RESULTS: In the comparison of patients with isolated BAV and those with BAV associated with repaired COA (n = 25 in each group), no differences were observed in left ventricular ejection fraction, GLS, or ventricular volumes, whilst significant increases in FCW and FEW magnitude were noted in the BAV and repaired COA group. The FCW inversely correlated with age and aortic size. Whilst the BCW was not significantly different compared with that in patients with/without COA, its magnitude tends to increase with a lower COA index. Patients with repaired COA exhibited higher wave speed velocity. Aortic wave speed (inversely related to distensibility) was not significantly different between the two groups. CONCLUSION: In the absence of a significant restenosis, VA coupling in patients with BAV and COA is not negatively affected compared to patients with isolated BAV. A reduction in the magnitude of the early systolic FCW was observed in patients who were older and with larger aortic diameters.

Results of comprehensive cardiovascular diagnostic work-up in HIV positive patients.

Cardiovascular disease (CVD) in the HIV population accounts for a large proportion of morbidity and mortality and, with the increased life expectancy, the burden of CVD is expected to rise. Inflammation, immune dysfunction, side effects of HIV medications, high prevalence of other risk factors are the likely pathogenic mechanisms for accelerated atherosclerosis. We aimed to evaluate the diagnostic yield of a cardiovascular multimodality diagnostic work-up in a contemporary cohort of HIV-infected patients. From November 2017 to October 2019, HIV infected patients were screened in a cardiovascular diagnostic work-up program including clinical history, physical examination, arterial blood pressure measurement, 12-lead ECG, and Transthoracic Echocardiogram (TTE). Advanced non-invasive cardiovascular imaging tests, like Coronary Computed Tomography Angiography (CCTA), stress-echocardiography, Cardiac Magnetic Resonance (CMR), were performed in patients with suspicion of chronic coronary syndrome (CCS) or non-ischemic heart disease (NIHD). 117 HIV-infected consecutive patients underwent this cardiovascular diagnostic work-up and were included in our study. Fifty-two patients (45%) had evidence of CVD. Of them, 22 presented Coronary Artery Disease (CAD), whereas 47 cases showed NIHD. In 17 cases both conditions were present. Among patients with CAD, 8 showed critical coronary stenosis; among them, 5 were treated with percutaneous coronary intervention, 2 with Aorto-Coronary By-Pass Grafting (CABG), and one with medical therapy. Hypertension and diabetes were significantly associated with the development of CVD (respectively p<0.001 and p< 0.05), while current smoking (p<0.02) and hypertension (p<0.007) were positively associated to CAD. A comprehensive cardiovascular diagnostic work-up including advanced multimodality diagnostic imaging modalities led to early detection of CVD in nearly half of an HIV population with immediate interventions required in 6.8% of them, and aggressive prevention treatment started in the remaining HIV patients.

Native T1 mapping to detect extent of acute and chronic myocardial infarction: comparison with late gadolinium enhancement technique.

Investigate whether native-T1 mapping can assess the transmural extent of myocardial infarction (TEI) thereby differentiating viable from non-viable myocardium without the use of gadolinium-contrast in both acute and chronic myocardial infarction (aMI and cMI). Sixty patients (30 cMI > 1 year and 30 aMI day 2 STEMI) and 20 healthy-controls underwent 1.5 T CMR to assess left ventricular function (cine), native-T1 mapping (MOLLI sequence 5(3)3, motion-corrected) and the presence and TEI from late gadolinium enhancement (LGE) images. Segments with TEI > 75% was considered non-viable. Gold-standard LGE-TEI was compared with corresponding segmental native-T1. Segmental native-T1 correlated significantly with TEI (R = 0.74, p < 0.001 in cMI and R = 0.57, p < 0.001 in aMI). Native-T1 differentiated segments with no LGE (1031 ± 31 ms), LGE positive but viable (1103 ± 57 ms) and LGE positive but non-viable (1206 ± 118 ms) in cMI (p < 0.01). It also differentiated segments with no LGE (1054 ± 65 m), LGE positive but viable (1135 ± 73 ms) and LGE positive but non-viable (1168 ± 71 ms) in aMI (p < 0.01). ROC analysis demonstrated excellent accuracy of native-T1 mapping compared to LGE-TEI (AUC - 0.88, p < 0.001 in cMI, vs AUC - 0.83, p < 0.001 in aMI). Native-T1 performed better in cMI than aMI (p < 0.01). In cMI a segmental T1 threshold of 1085 ms differentiated viable from non-viable segments with a sensitivity 88% and specificity of 88% whereas a T1 of 1110 ms differentiated viable from nonviable with 79% sensitivity and 79% specificity in aMI. Native-T1 mapping correlates significantly with TEI thereby differentiating between normal, viable, and non-viable myocardium with distinctive T1 profiles in aMI and cMI. Native T1-mapping to detect MI performed better in cMI compared to aMI due to absence of myocardial oedema. Native-T1 mapping holds promise for viability assessment without the need for gadolinium-contrast agent.

Beyond apical ballooning: computational modelling reveals morphological features of Takotsubo cardiomyopathy.

Takotsubo cardiomyopathy (TCM) is characterized by transient myocardial dysfunction, typically at the left ventricular (LV) apex. Its pathophysiology and recovery mechanisms remain unknown. We investigated LV morphology and deformation in n = 28 TCM patients. Patients with MRI within 5 days from admission ("early TCM") showed reduced LVEF and higher ventricular volumes, but no differences in ECG, global strains or myocardial oedema. Statistical shape modelling described LV size (Mode 1), apical sphericity (Mode 2) and height (Mode 3). Significant differences in Mode 1 suggest that "early TCM" LV remodeling is mainly influenced by a change in ventricular size rather than apical sphericity.

Enlightening the Association between Bicuspid Aortic Valve and Aortopathy.

Bicuspid aortic valve (BAV) patients have an increased incidence of developing aortic dilation. Despite its importance, the pathogenesis of aortopathy in BAV is still largely undetermined. Nowadays, intense focus falls both on BAV morphology and progression of valvular dysfunction and on the development of aortic dilation. However, less is known about the relationship between aortic valve morphology and aortic dilation. A better understanding of the molecular pathways involved in the homeostasis of the aortic wall, including the extracellular matrix, the plasticity of the vascular smooth cells, TGFβ signaling, and epigenetic dysregulation, is key to enlighten the mechanisms underpinning BAV-aortopathy development and progression. To date, there are two main theories on this subject, i.e., the genetic and the hemodynamic theory, with an ongoing debate over the pathogenesis of BAV-aortopathy. Furthermore, the lack of early detection biomarkers leads to challenges in the management of patients affected by BAV-aortopathy. Here, we critically review the current knowledge on the driving mechanisms of BAV-aortopathy together with the current clinical management and lack of available biomarkers allowing for early detection and better treatment optimization.