The extent and location of late gadolinium enhancement predict defibrillator shock and cardiac mortality in patients with non-ischaemic dilated cardiomyopathy

BACKGROUND

In non-ischaemic dilated cardiomyopathy (NIDCM), it is uncertain which late gadolinium enhancement (LGE) pattern, extent and location predict ventricular arrhythmias.

METHODS

We analysed 183 NIDCM patients (73% men, median age 66 years) receiving an implantable cardioverter defibrillator (ICD) for primary prevention, undergoing cardiac magnetic resonance within 1 month before implantation. The primary endpoint was appropriate ICD shock, the secondary endpoint was a composite of appropriate ICD shock and cardiac death.

RESULTS

LGE was found in 116 patients (63%), accounting for 9% of LV mass (5-13%). Over a 30-month follow-up (10-65), 20 patients (11%) experienced the primary and 30 patients (16%) the secondary endpoint. LGE presence, inferior wall LGE, diffuse (≥2 wall) LGE, the number of segments with LGE, the number of segments with 50-75% transmural LGE, and percent LGE mass were univariate predictors of both endpoints. Also septal LGE predicted the primary, and lateral LGE predicted the secondary endpoint. LGE limited to right ventricular insertion points did not predict any endpoint. Percent LGE mass had an area under the curve of 0.734 for the primary endpoint, with 13% as the best cut-off (55% sensitivity, 86% specificity, 32% PPV, 94% NPV), conferring a 7-fold higher risk compared to patients with no LGE or LGE <13%. Survival free from both endpoints was significantly worse for patients with LGE ≥13%.

CONCLUSIONS

In patients with NIDCM receiving a defibrillator for primary prevention, LGE presence and extent predicted appropriate ICD shock and cardiac mortality; also specific LGE patterns and locations predicted a worse prognosis.

What Is Hidden Behind Inferior Negative T Waves: Multiple Cardiac Glomangiomas

Negative T waves in the inferior leads in an asymptomatic 17-year-old female patient prompted a diagnostic evaluation disclosing the presence of multiple cardiac glomangiomas. The combination of different imaging modalities (echocardiography, magnetic resonance, and positron emission tomography/computed tomography) and myocardial biopsy was crucial to establishing the correct diagnosis. (Level of Difficulty: Advanced.).

Prognostic relevance of pericardial effusion in STEMI patients treated by primary percutaneous coronary intervention: a 10-year single-centre experience

BACKGROUND

Pericardial effusion is frequent in the acute phase of ST-segment elevation myocardial infarction. However, its prognostic role in the era of primary percutaneous coronary intervention is not completely understood.

METHODS

We investigated the association between pericardial effusion, assessed by transthoracic echocardiography, and survival in a large cohort of ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention, enrolled in the Trieste primary percutaneous coronary intervention registry from January 2007 to March 2017. Multivariable analysis and a propensity score approach were performed.

RESULTS

A total of 1732 ST-segment elevation myocardial infarction patients were included. Median follow-up was 45 (interquartile range 19-79) months. Pericardial effusion was present in 246 patients (14.2%). Thirty-day all-cause mortality was similar between patients with and without pericardial effusion (7.8% vs. 5.4%, P=0.15), whereas crude long-term survival was worse in patients with pericardial effusion (26.2% vs. 17.7%, P≤0.01). However, at multivariable analyses the presence of pericardial effusion was not associated with long-term mortality (hazard ratio 1.26, 95% confidence interval 0.86-1.82, P=0.22). Matching based on propensity scores confirmed the lack of association between pericardial effusion and both 30-day (hazard ratio 1, 95% confidence interval 0.42-2.36, P=1) and long-term (hazard ratio 1.14, 95% confidence interval 0.74-1.78, P=0.53) all-cause mortality. Patients with pericardial effusion experienced a higher incidence of free wall rupture (2.8% vs. 0.5%, P<0.0001) independently of the entity of pericardial effusion.

CONCLUSIONS

In acute ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention, the onset of pericardial effusion after ST-segment elevation myocardial infarction is not independently associated with short and long-term higher mortality. Free wall rupture has to be considered rare compared to the fibrinolytic era and occurs more frequently in patients with pericardial effusion, suggesting a close monitoring of these patients in the early post-primary percutaneous coronary intervention phase.

P995The extent of late gadolinium enhancement predicts defibrillator shocks in patients with non-ischaemic heart failure

Background

Implantable cardioverter defibrillator (ICD) is recommended for patients with non-ischaemic heart failure (HF) and left ventricular ejection fraction (LVEF) ≤35%, although most patients will not experience any appropriate ICD intervention. We assessed if cardiovascular magnetic resonance (CMR) findings may predict benefit from ICD implantation.

Methods and results

We retrieved the data of all patients (n=183) with non-ischaemic HF receiving an ICD for primary prevention at our Institution, and undergoing CMR within 1 month before implantation. 183 patients were evaluated (men 73%, median age 66 years, LVEF 24%, N-terminal fraction of pro-B-type natriuretic peptide 1217 ng/L, atrial fibrillation, flutter or atrial ectopic rhythm 21%). They received single-chamber (n=21, 12%), dual-chamber (n=34, 19%), or cardiac resynchronization therapy devices (n=127, 69%); 1 patient (1%) received a subcutaneous defibrillator. Twenty patients (11%) experienced a shock for ventricular tachycardia or fibrillation (VT/VF) over 2.5 years (0.8–5.4), and 13 (7%) had an inappropriate shock over 2.7 years (0.9–5.4). Late gadolinium enhancement (LGE) was present in 146 patients (80%), but on average accounted for limited percentage of LV mass (4% [2–11%]). LGE mass independently predicted shocks for VT/VF (HR 2.13, 95% CI 1.02–4.47; p=0.045). LGE mass ≥14% (the best cut-off at receiver operating characteristics analysis) independently predicted shocks for VT/VF (HR 3.82, 95% CI 1.51–9.68; p=0.005). LGE mass <4% was the only univariate predictor of inappropriate shocks (HR 4.82, 95% CI 1.07–21.76; p=0.041).

Conclusions

Patients with non-ischaemic HF and LGE mass ≥14% benefit most from ICD, while those with LGE mass <4% display mainly inappropriate shocks.

P597Clinical and prognostic correlates of volume/time curve at cardiac magnetic resonance in patients with non-ischemic heart failure and left bundle branch block

Background

In patients with non-ischaemic systolic heart failure (HF) and left bundle branch block (LBBB), the systolic phase of the left ventricular (LV) volume/time (V/t) curve at cardiac magnetic resonance (CMR) can display a wide or a narrow pattern (WP/NP). The clinical and prognostic significance of these patterns are currently unknown.

Methods

Consecutive patients with systolic non-ischaemic HF (LV ejection fraction <50%) and LBBB were enrolled. They underwent a baseline evaluation including CMR, and were periodically re-evaluated during follow-up. The endpoint was a composite of cardiovascular death, heart failure (HF)-related event, and ventricular arrhythmias requiring defibrillator shock.

Results

Out of 101 patients (mean age 64±11 years, males 50%), NP was found in 29 and WP in 72, with no difference in QRS duration. Patients with WP had worse clinical presentation and greater LV volumes, but similar LGE prevalence, extent or distribution. The WP subgroup displayed a greater maximal dyssynchrony time, expressed both as absolute duration (192±80 vs. 143±65 ms, P<0.001), and as percentage of the RR interval (25±11% vs. 8±4%, p<0.001). Even the systolic dyssynchrony index was higher in patients with WP (13±4 vs. 7±3%, p<0.001). The contractility index was lower in patients with the WP (2.6±1.2 vs 3.2±1.7, p<0.05). Over a median follow-up duration of 44 months (interquartile interval 23–59), only WP (p=0.029) and NT-proBNP (p=0.004) demonstrated an independent prognostic value for cardiac events.

Conclusions

In patients with non-ischaemic systolic HF and LBBB, the WP of V/t curves identifies a subgroup of patients with greater LV dyssynchrony, worse clinical conditions and prognosis.

P2728Prognostic impact of left atrial function in patients with cardiac amyloidosis: a cardiac magnetic resonance study

Background

Left atrial function (AEF) is a parameter of paramount importance that has a prognostic value in a number of heart conditions. Cardiac involvement in both light-chain and transthyretin amyloidosis is the main driver of prognosis and influences treatment strategies. Cardiac magnetic resonance (CMR) provides high quality images of the left and right atria using high temporal resolution steady state free precession (SSFP) cine sequences.

Purpose

The aim of our study was to assess by CMR left atrial function and his correlation with prognosis in patients with cardiac amyloidosis.

Method

We enrolled 80 consecutive patients with diagnosis of cardiac amyloidosis: 38 patients (47%) with light-chain and 42 patients (53%) with transthyretin one. CMR was performed using a 1.5-T scanner. In all subjects, the study of atria was obtained by acquiring cine steady-state free precession (SSFP). Left Atrial function was evaluated by the ratio between the maximum and the minimum LA volume. A median follow up of 937 days was performed and 36 patients (44%) died of cardiac causes. We evaluated cardiac death as endpoint. We split out all the patient in 4 different quartiles depending on left atrial function: in the first quartile patients with AEF≤14% that reflects severe atrial dysfunction, in the second quartile patients with AEF between 14 and 19%, in the third quartile patients with AEF between 19 and 36% and in the last one patients with AEF≥36% that represent patients with normal value of left atrial function.

Results

We found that CMR assessed left atrial function allowed to individuate and stratify the prognosis in patients with cardiac amyloidosis. The most effective parameter to evaluate cardiac death was left atrial function with a cut off ≤14% that could predict cardiac related mortality with the same accuracy in both light-chain and transthyretin amyloidosis patients. Kaplan Meier analysis showed that patients with AEF≤14% had a worse prognosis as compared to patient with AEF≥14% (log rank p. 0001). Furthermore patients with AEF≤14% have a cardiac death risk of 32% at 1 year and 61% at 3 years.

Kaplan Meier analysis

Conclusion

Cardiac magnetic resonance is an imaging modality that allows to individuate with great accuracy left atrial function in patients with various heart conditions and especially cardiac amyloidosis. CMR left atrial function assessment clearly identifies a subgroup of cardiac amyloid patients with an increased risk of death.

Functional Magnetic Resonance Imaging in the Evaluation of the Elastic Properties of Ascending Aortic Aneurysm

Objective

To evaluate the aortic wall elasticity using the maximal rate of systolic distension (MRSD) and maximal rate of diastolic recoil (MRDR) and their correlation with the aortic size index (ASI).

Methods

Forty-eight patients with thoracic aortic aneurysm were enrolled in this study. A standard magnetic resonance imaging (MRI) protocol was used to calculate MRSD and MRDR. Both MRSD and MRDR were expressed as percentile of maximal area/10^-3 sec. ASI (maximal aortic diameter/body surface area) was calculated. A correlation between MRSD, MRDR, ASI, and the patient’s age was performed using regression plot.

Results

A significant correlation between MRSD (t=-4,36; r²=0.29; P≤0.0001), MRDR (t=3.92; r²=0.25; P=0.0003), and ASI (25±4.33 mm/m²; range 15,48-35,14 mm/m²) is observed. As ASI increases, aortic MRSD and MRDR decrease. Such inverse correlation between MRSD, MRDR, and ASI indicates increased stiffness of the ascending aorta. A significant correlation between the patient’s age and the decrease in MRSD and MRDR is observed.

Conclusion

MRSD and MRDR are significantly correlated with ASI and the patient’s age. They seem to describe properly the increasing stiffness of aortas. These two new indexes provide a promising, accessible, and reproducible approach to evaluate the biomechanical property of the aorta.

MicroRNA therapy stimulates uncontrolled cardiac repair after myocardial infarction in pigs

Prompt coronary catheterization and revascularization have dramatically improved the outcome of myocardial infarction, but also have resulted in a growing number of survived patients with permanent structural damage of the heart, which frequently leads to heart failure. Finding new treatments for this condition is a largely unmet clinical need 1, especially because of the incapacity of cardiomyocytes to replicate after birth and thus achieve regeneration of the lost contractile tissue 2. Here we show that expression of human microRNA-199a in infarcted pig hearts is capable of stimulating cardiac repair. One month after myocardial infarction and delivery of this microRNA through an adeno-associated viral vector, the treated animals showed marked improvements in both global and regional contractility, increased muscle mass and reduced scar size. These functional and morphological findings correlated with cardiomyocyte de-differentiation and proliferation. At longer follow-up, however, persistent and uncontrolled expression of the microRNA resulted in sudden arrhythmic death of most of the treated pigs. Such events were concurrent with myocardial infiltration of proliferating cells displaying a poorly differentiated myoblastic phenotype. These results show that achieving cardiac repair through the stimulation of endogenous cardiomyocyte proliferation is attainable in large mammals, however this therapy needs to be tightly dosed.

Usefulness of Triiodothyronine Replacement Therapy in Patients With ST Elevation Myocardial Infarction and Borderline/Reduced Triiodothyronine Levels (from the THIRST Study)

The aim of the study was to investigate whether TH replacement therapy is safe and impact infarct size, left ventricular (LV) volumes and function in patients with acute myocardial infarction (AMI) and low T3 syndrome (LT3S). Thirty-seven AMI/LT3S patients were randomly treated or untreated with liothyronine (T3) therapy (maximum dosage 15 mcg/m²/die) in addition to standardized treatment (T3-treated group, n = 19; untreated group, n = 18). TH and thyroxine (TSH) during hospital stay and at 1-month and 6 months were evaluated. At discharge and at 6 months LV volumes, ejection fraction, wall motion score index (WMSI) and infarct extent were measured by cardiac MR. T3-treated patients had a significant increase in fT3 (p = 0.003 and p <0.001) at discharge and 1-month. These patients had no signs or symptoms of hyperthyroidism or arrhythmias. At follow-up, there was a significant reduction in WMSI in both groups (T3-treated group: Δ = -0.12, p = 0.001; untreated group: Δ = -0.04, p = 0.04) and the difference value (discharge/follow-up) was significantly higher in T3-treated group than in untreated group (mean difference between groups = 0.08, 95% confidence interval [CI]: 0.01 to 0.15, p = 0.05). Also, stroke volume increased significantly in the T3-treated group (Δ = 3.4, 95% CI: 0.8 to 6, p <0.01) at follow-up. In conclusion, this is the first pilot experience in which T3 replacement therapy resulted safe and able to improve regional dysfunction in patients with STEMI/LT3S.

Cardiovascular magnetic resonance imaging in hypertrophic cardiomyopathy: the importance of clinical context

In patients with suspected or established hypertrophic cardiomyopathy (HCM), cardiovascular magnetic resonance (CMR) is widely employed for clinical management, given its multimodality approach capable of providing unique information on cardiac morphology, function, and tissue characterization. Guidance regarding all aspects of HCM diagnosis and management is provided by the comprehensive 2014 European Society of Cardiology (ESC) guidelines on HCM. CMR should be performed in centres with recognized expertise in heart muscle diseases, by physicians who are familiar with the whole HCM disease spectrum, differential diagnoses, and pitfalls. Because CMR is usually performed and interpreted by physicians not directly involved in patient care, detailed, bidirectional, and standardized communication becomes essential to obtain best results and avoid misinterpretation. In order to maximize the potential of CMR, it is of paramount importance that reporting physicians are provided with the essential clinical information and that, in turn, referring physicians are given a core set of CMR morphological, functional, and tissue characterization results following the test. This article aims to summarize the current knowledge on the role of CMR in managing HCM and, in addition, to review the importance of the clinical context in which the report is provided, in both adult and paediatric population, highlighting implications for clinical research.

Prognostic Role of Cardiac Magnetic Resonance in Arrhythmogenic Right Ventricular Cardiomyopathy

We sought to evaluate the prognostic role of cardiac magnetic resonance (CMR) in patients with definite, borderline and possible diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) as defined by the International Task Force (TF) in 2010. CMR was performed in 175 patients: 52 with definite, 50 with borderline and 73 possible ARVC. Abnormal-CMR was defined as the presence of ≥1 CMR abnormalities (including abnormalities of right ventricular and left ventricular wall motion, fat infiltration, late gadolinium enhancement, dilation and dysfunction of either ventricles). During the follow-up time 35 patients had hard cardiac events (sudden cardiac death, appropriate implantable cardioverter defibrillator shock and resuscitated cardiac arrest), and 34 of them occurred in patients with abnormal-CMR (negative predictive value = 96.9%). At the multivariate Cox-regression analysis LV involvement at CMR (fat infiltration and/or late gadolinium enhancement), and episode of nonsustained ventricular tachycardia (NSVT) were independent predictors of cardiac events in both the whole population (LV involvement: HR 3.69, 95% CI 1.57-8.65, p = 0.0002; NSVT: HR 5.8, 95% CI 2.82-11.9, p < 0.0001), and in the group of patients with definite ARVC (LV involvement: HR 3.03, 95% CI 1.15 to 8.02, p = 0.02; NSVT: HR 12.1, 95% CI 4.02-36.5, p < 0.0001). In conclusion, CMR evidence of LV involvement is a strong independent predictor of cardiac events in patients with definite, borderline or possible ARVC diagnosis. Abnormal CMR has very high negative predictive value for hard cardiac events.

Advanced imaging techniques (CT and MR): Gender-based diagnostic work-up in ischemic heart disease?

It is ascertained that the epidemiology and social impact of ischemic heart disease is substantially different between the two genders. Moreover, there is substantial evidence that gender is able to modulate the clinical manifestation of most cardiac diseases, and specifically of coronary artery disease. Particularly, women present less angiographically significant coronary artery disease, smaller vessel lumen, and less plaque rupture occurrence as compared to men. On the contrary, manifestations as vasospasm, impaired vasodilatation at epicardial level, and microvascular dysfunction are more common in female. In clinical practice, it is important to know the gender-based aspects of clinical disease expression and how to diversify the diagnostic work-up. Cardiac Computed Tomography and Cardiac Magnetic Resonance are relatively new diagnostic imaging tools employed for studying both the cardiac structures and the pathophysiology of the cardiovascular system. In this paper, we aim to overview the non-invasive diagnostic role in a gender's dimension, mainly focusing on Cardiac Computed Tomography and Cardiac Magnetic Resonance in ischemic heart disease, and to understand whether the existing evidences support a different diagnostic work-up approach.

Pericardial Agenesis as a Rather Unusual Cause of Palpitations: We Only See What we Know

Cardiac palpitations secondary to ventricular ectopic beats are a frequent clinical indication for a cardiac magnetic resonance (CMR) scan. CMR has already demonstrated its additive diagnostic value in patients with frequent arrhythmias even when echocardiogram appears normal. Hereby, we describe a case of a middle-aged male patient referred to our laboratory because of frequent ventricular ectopic beats and an inconclusive echocardiogram due to an extremely poor acoustic window. A diagnosis of pericardial agenesis (PA) was made explaining patient symptoms and arrhythmias previously detected. Furthermore, at the case report description, PA prevalence, associated cardiac pathologies, and novel CMR diagnostic criteria are being described.

Diastolic dysfunction evaluated by cardiac magnetic resonance: the value of the combined assessment of atrial and ventricular function

OBJECTIVES

We sought to evaluate the role of cardiac magnetic resonance imaging (CMR) in the evaluation of diastolic function by a combined assessment of left ventricular (LV) and left atrial (LA) function in a cohort of subjects with various degrees of diastolic dysfunction (DD) detected by echocardiography.

METHODS

Forty patients with different stages of DD and 18 healthy controls underwent CMR. Short-axis cine steady-state free precession images covering the entire LA and LV were acquired. Parameters of diastolic function were measured by the analysis of the LV and LA volume/time (V/t) curves and the respective derivative dV/dt curves.

RESULTS

At receiver operating characteristic (ROC) curve analysis, the peak of emptying rate A indexed by the LV filling volume with a cut-off of 3.8 was able to detect patients with grade I DD from other groups (area under the curve [AUC] 0.975, 95% confidence interval [CI] 0.86-1). ROC analysis showed that LA ejection fraction with a cut-off of ≤36% was able to distinguish controls and grade I DD patients from those with grade II and grade III DD (AUC 0.996, 95% CI 0.92-1, p < 0.001). The isovolumetric pulmonary vein transit ratio with a cut-off of 2.4 allowed class III DD to be distinguished from other groups (AUC 1.0, 95%CI 0.93-1, p < 0.001).

CONCLUSIONS

Analysis of LV and LA V/t curves by CMR may be useful for the evaluation of DD.

KEY POINTS

• Combined atrial and ventricular volume/time curves allow evaluation of diastolic function. • Atrial emptying fraction allows distinction between impaired relaxation and restrictive/pseudo-normal filling. • Isovolumetric pulmonary vein transit ratio allows distinction between restrictive and pseudo-normal filling.