Severe Aortic Stenosis in a Pregnant Patient Displaced by the Ukrainian-Russian War.

We describe the complex case of a 32-year-old pregnant woman with known severe aortic stenosis, who was displaced by the Ukrainian-Russian War. She arrived in the United Kingdom at 32 weeks' gestation speaking minimal English, but requiring urgent multidisciplinary care to facilitate appropriate antenatal, peripartum, and postpartum care.

Therapeutic Dilemmas Faced When Managing a Life-Threatening Presentation of a Myocardial Bridge.

Background. Myocardial bridges are congenital abnormalities, where a segment of coronary artery travels intramyocardially, rather than the typical epicardial course. The overlying muscle segment is termed "the bridge". Most myocardial bridges are asymptomatic, but some can result in myocardial ischaemia, arrhythmias, and sudden cardiac death. Case Presentation. A 31-year-old male with no past medical history presented to our tertiary cardiac centre following an out-of-hospital ventricular fibrillation arrest. Coronary angiography and computed tomography of the coronary arteries revealed a 2 cm myocardial bridge overlying the left anterior descending (LAD) artery. An exercise echocardiogram demonstrated severe apical ballooning and hypokinesis during peak exercise, with corresponding ST-segment elevation, resolving on rest. Options for medical therapy of a symptomatic myocardial bridge include beta blockers, calcium channel blockers, ivabradine, or a combination thereof. Surgical interventions include deroofing the bridge and revascularisation of the affected region with bypass grafting. However, a lack of trial data comparing medical regimens and surgical interventions makes it difficult to ascertain the most effective management strategy for each patient. There was disagreement between experts at different tertiary centres over the optimal management of this patient. He was treated with multiple regimes of medical therapy with ongoing ischaemia on stress testing, before undergoing a negative stress test on amlodipine, diltiazem, and isosorbide mononitrate. It was felt that no further intervention was necessary at this time given his exercise test was now negative for ischaemia. However, after seeking a second opinion, he underwent surgical intervention with bypass grafting of his left anterior descending artery, followed by implantation of an implantable cardiac defibrillator. Subsequently, an angiogram postsurgery demonstrated concomitant spasm of the LAD and he was resumed on medical therapy with calcium channel blockers and nitrates. Discussion. Without randomised trials, it is impossible to determine the optimal management strategy for each patient. It is possible that some patients with myocardial bridges are not being trialled on optimal medical therapy prior to undergoing invasive and irreversible interventions.

Cardiac Computed Tomography: Application in Valvular Heart Disease.

The incidence and prevalence of valvular heart disease (VHD) is increasing and has been described as the next cardiac epidemic. Advances in imaging and therapeutics have revolutionized how we assess and treat patients with VHD. Although echocardiography continues to be the first-line imaging modality to assess the severity and the effects of VHD, advances in cardiac computed tomography (CT) now provide novel insights into VHD. Transcatheter valvular interventions rely heavily on CT guidance for procedural planning, predicting and detecting complications, and monitoring prosthesis. This review focuses on the current role and future prospects of CT in the assessment of aortic and mitral valves for transcatheter interventions, prosthetic valve complications such as thrombosis and endocarditis, and assessment of the myocardium.

Cardiac magnetic resonance imaging in preeclampsia complicated by pulmonary edema shows myocardial edema with normal left ventricular systolic function.

BACKGROUND: Preeclampsia complicates approximately 5% of all pregnancies. When pulmonary edema occurs, it accounts for 50% of preeclampsia-related mortality. Currently, there is no consensus on the degree to which left ventricular systolic dysfunction contributes to the development of pulmonary edema. OBJECTIVE: This study aimed to use cardiac magnetic resonance imaging to detect subtle changes in left ventricular systolic function and evidence of acute left ventricular dysfunction (through tissue characterization) in women with preeclampsia complicated by pulmonary edema compared with both preeclamptic and normotensive controls. STUDY DESIGN: Cases were postpartum women aged ≥18 years presenting with preeclampsia complicated by pulmonary edema. Of note, 2 control groups were recruited: women with preeclampsia without pulmonary edema and women with normotensive pregnancies. All women underwent echocardiography and 1.5T cardiac magnetic resonance imaging with native T1 and T2 mapping. Gadolinium contrast was administered to cases only. Because of small sample sizes, a nonparametric test (Kruskal-Wallis) with pairwise posthoc analysis using Bonferroni correction was used to compare the differences between the groups. Cardiac magnetic resonance images were interpreted by 2 independent reporters. The intraclass correlation coefficient was calculated to assess interobserver reliability. RESULTS: Here, 20 women with preeclampsia complicated by pulmonary edema, 13 women with preeclampsia (5 with severe features and 8 without severe features), and 6 normotensive controls were recruited. There was no difference in the baseline characteristics between groups apart from the expected differences in blood pressure. Left atrial sizes were similar across all groups. Women with preeclampsia complicated by pulmonary edema had increased left ventricular mass (P=.01) but had normal systolic function compared with the normotensive controls. Furthermore, they had elevated native T1 values (P=.025) and a trend toward elevated T2 values (P=.07) in the absence of late gadolinium enhancement consistent with myocardial edema. Moreover, myocardial edema was present in all women with eclampsia or hemolysis, elevated liver enzymes, and low platelet count. Women with preeclampsia without severe features had similar findings to the normotensive controls. All cardiac magnetic resonance imaging measurements showed a very high level of interobserver correlation. CONCLUSION: This study focused on cardiac magnetic resonance imaging in women with preeclampsia complicated by pulmonary edema, eclampsia, and hemolysis, elevated liver enzymes, and low platelet count. We have demonstrated normal systolic function with myocardial edema in women with preeclampsia with these severe features. These findings implicate an acute myocardial process as part of this clinical syndrome. The pathogenesis of myocardial edema and its relationship to pulmonary edema require further elucidation. With normal left atrial sizes, any hemodynamic component must be acute.

Effects of Spironolactone and Chlorthalidone on Cardiovascular Structure and Function in Chronic Kidney Disease: A Randomized, Open-Label Trial.

BACKGROUND AND OBJECTIVES: In a randomized double-blind, placebo-controlled trial, treatment with spironolactone in early-stage CKD reduced left ventricular mass and arterial stiffness compared with placebo. It is not known if these effects were due to BP reduction or specific vascular and myocardial effects of spironolactone. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A prospective, randomized, open-label, blinded end point study conducted in four UK centers (Birmingham, Cambridge, Edinburgh, and London) comparing spironolactone 25 mg to chlorthalidone 25 mg once daily for 40 weeks in 154 participants with nondiabetic stage 2 and 3 CKD (eGFR 30-89 ml/min per 1.73 m2). The primary end point was change in left ventricular mass on cardiac magnetic resonance imaging. Participants were on treatment with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker and had controlled BP (target ≤130/80 mm Hg). RESULTS: There was no significant difference in left ventricular mass regression; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was -3.8 g (95% confidence interval, -8.1 to 0.5 g, P=0.08). Office and 24-hour ambulatory BPs fell in response to both drugs with no significant differences between treatment. Pulse wave velocity was not significantly different between groups; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was 0.04 m/s (-0.4 m/s, 0.5 m/s, P=0.90). Hyperkalemia (defined ≥5.4 mEq/L) occurred more frequently with spironolactone (12 versus two participants, adjusted relative risk was 5.5, 95% confidence interval, 1.4 to 22.1, P=0.02), but there were no patients with severe hyperkalemia (defined ≥6.5 mEq/L). A decline in eGFR >30% occurred in eight participants treated with chlorthalidone compared with two participants with spironolactone (adjusted relative risk was 0.2, 95% confidence interval, 0.05 to 1.1, P=0.07). CONCLUSIONS: Spironolactone was not superior to chlorthalidone in reducing left ventricular mass, BP, or arterial stiffness in nondiabetic CKD.

Noninvasive rapid cardiac magnetic resonance for the assessment of cardiomyopathies in low-middle income countries.

Introduction: Cardiac Magnetic Resonance (CMR) is a crucial diagnostic imaging test that redefines diagnosis and enables targeted therapies, but the access to CMR is limited in low-middle Income Countries (LMICs) even though cardiovascular disease is an emergent primary cause of mortality in LMICs. New abbreviated CMR protocols can be less expensive, faster, whilst maintaining accuracy, potentially leading to a higher utilization in LMICs.Areas covered: This article will review cardiovascular disease in LMICs and the current role of CMR in cardiac diagnosis and enable targeted therapy, discussing the main obstacles to prevent the adoption of CMR in LMICs. We will then review the potential utility of abbreviated, cost-effective CMR protocols to improve cardiac diagnosis and care, the clinical indications of the exam, current evidence and future directions.Expert opinion: Rapid CMR protocols, provided that they are utilized in potentially high yield cases, could reduce cost and increase effectiveness. The adoption of these protocols, their integration into care pathways, and prioritizing key treatable diagnoses can potentially improve patient care. Several LMIC countries are now pioneering these approaches and the application of rapid CMR protocols appears to have a bright future if delivered effectively.

Apical hypertrophic cardiomyopathy associated with circumflex to left ventricular fistulae: a case report of two rare subtypes of rare conditions occurring together.

BACKGROUND: Coronary arterial fistulae are rare yet have been associated with hypertrophic cardiomyopathy (HCM). We present a patient who was found to have a left circumflex (LCx) to left ventricular (LV) fistula in combination with apical HCM. CASE SUMMARY: A 72-year-old female presented with syncope after exercise. She sustained facial injuries including fracture of her nasal bones. There were no previous episodes, no cardiac history, and she denied chest pain or anginal symptoms. Electrocardiogram showed sinus rhythm with T-wave inversion throughout the chest leads. Echocardiography suggested apical HCM with hypertrophy of the LV apex but good systolic function. This was confirmed on cardiac magnetic resonance imaging with a characteristically spade-shaped LV cavity. Coronary angiography demonstrated a distal LCx to LV fistula from the apical hypertrophy but no coronary artery disease. She was started on beta-blockers and has had no further episodes, remaining well. DISCUSSION: Coronary fistulae are present in 0.002% of the population but clinical outcomes are poorly understood. The majority are asymptomatic but anginal chest pains can occur through the 'coronary steal' phenomenon. Apical HCM is a subtype of HCM characterized by spade-shaped LV cavity obliteration. It is unclear whether the association between fistulae and HCM occur because of the increased vascularization and fibrosis associated with HCM or whether congenital malformation leads to hypertrophy. Both can produce a constellation of cardiac symptoms. Our patient has the previously unreported combination of apical HCM and an LCx fistula; two rarer subtypes of rare conditions appearing together.

Cardiovascular magnetic resonance can be undertaken in pregnancy and guide clinical decision-making in this patient population.

AIMS: Cardiovascular disease is the leading cause of maternal morbidity and mortality, frequently requiring cardiac imaging for diagnosis, and follow-up. This need does not change pregnancy; however, many centres do not offer cardiovascular magnetic resonance (CMR) to pregnant patients. This paper explores current practice of CMR in pregnancy in four large volume centres, its safety and its impact on patient management. METHODS AND RESULTS: Between 2008 and 2017, we collected consecutive pregnant patients between four centres. Guidelines and local standard operating procedures were followed and outcomes recorded modelled on the EuroCMR registry. Eighty-three women had diagnostic CMR without immediate complications. The commonest indication was vascular or congenital disease (48%), followed by cardiomyopathy/myocarditis (43%). Nineteen percent received contrast, and CMR changed management in 35% and in 50% of patients who received contrast. CONCLUSION: In this largest cohort to date describing CMR in pregnancy, we found that results frequently change management, thus adding valuable guidance for patient care. We conclude that CMR should be offered to pregnant women when indicated, including the administration of contrast as per current guidelines.

Myocardial native T1 and extracellular volume with healthy ageing and gender.

Aims: To determine how native myocardial T1 and extracellular volume (ECV) change with age, both to understand aging and to inform on normal reference ranges. Methods and results: Ninety-four healthy volunteers with no a history or symptoms of cardiovascular disease or diabetes underwent cardiovascular magnetic resonance at 1.5 T. Mid-ventricular short axis native and post-contrast T1 maps by Shortened MOdified Look-Locker Inversion-recovery (ShMOLLI), MOdified Look-Locker Inversion Recovery (MOLLI) [pre-contrast: 5s(3s)3s, post-contrast: 4s(1s)3s(1s)2s] and saturation recovery single-shot acquisition (SASHA) were acquired and ECV by these three techniques were derived for the mid anteroseptum. Mean age was 50 ± 14 years (range 20-76), male 52%, with no age difference between genders (males 51 ± 14 years; females 49 ± 15 years, P = 0.55). Quoting respectively ShMOLLI, MOLLI, SASHA throughout, mean myocardial T1 was 957 ± 30 ms, 1025 ± 38 ms, 1144 ± 45 ms (P < 0.0001) and ECV 28.4 ± 3.0% [95% confidence interval (CI) 27.8-29.0], 27.3 ± 2.7 (95% CI 26.8-27.9), 24.1 ± 2.9% (95% CI 23.5-24.7) (P < 0.0001), with all values higher in females for all techniques (T1 +18 ms, +35 ms, +51 ms; ECV +2.7%, +2.6%, +3.4%). Native myocardial T1 reduced slightly with age (R2 = 0.042, P = 0.048; R2 = 0.131, P < 0.0001-on average by 8-11 ms/decade-but not for SASHA (R2 = 0.033 and P = 0.083). ECV did not change with age (R2 = 0.003, P = 0.582; R2 = 0.002, P = 0.689; R2 = 0.003, P = 0.615). Heart rate decreased slightly with age (R2 = 0.075, coefficient = -0.273, P = 0.008), but there was no relationship between age and other blood T1 influences (haematocrit, iron, high density lipoprotein-cholesterol). Conclusion: Gender influences native T1 and ECV with women having a higher native T1 and ECV. Native T1 measured by MOLLI and ShMOLLI was slightly lower with increasing age but not with SASHA and ECV was independent of age for all techniques.

Redefining viability by cardiovascular magnetic resonance in acute ST-segment elevation myocardial infarction.

In chronic myocardial infarction (MI), segments with a transmural extent of infarct (TEI) of ≤50% are defined as being viable. However, in the acute phase of an ST-segment elevation myocardial infarction (STEMI), late gadolinium enhancement (LGE) has been demonstrated to overestimate MI size and TEI. We aimed to identify the optimal cut-off of TEI by cardiovascular magnetic resonance (CMR) for defining viability during the acute phase of an MI, using ≤50% TEI at follow-up as the reference standard. 40 STEMI patients reperfused by primary percutaneous coronary intervention (PPCI) underwent a CMR at 4 ± 2 days and 5 ± 2 months. The large majority of segments with 1-25%TEI and 26-50%TEI that were viable acutely were also viable at follow-up (59/59, 100% and 75/82, 96% viable respectively). 56/84(67%) segments with 51-75%TEI but only 4/63(6%) segments with 76-100%TEI were reclassified as viable at follow-up. TEI on the acute CMR scan had an area-under-the-curve of 0.87 (95% confidence interval of 0.82 to 0.91) and ≤75%TEI had a sensitivity of 98% but a specificity of 66% to predict viability at follow-up. Therefore, the optimal cut-off by CMR during the acute phase of an MI to predict viability was ≤75% TEI and this would have important implications for patients undergoing viability testing prior to revascularization during the acute phase.

Quantification of both the area-at-risk and acute myocardial infarct size in ST-segment elevation myocardial infarction using T1-mapping.

BACKGROUND: A comprehensive cardiovascular magnetic resonance (CMR) in reperfused ST-segment myocardial infarction (STEMI) patients can be challenging to perform and can be time-consuming. We aimed to investigate whether native T1-mapping can accurately delineate the edema-based area-at-risk (AAR) and post-contrast T1-mapping and synthetic late gadolinium (LGE) images can quantify MI size at 1.5 T. Conventional LGE imaging and T2-mapping could then be omitted, thereby shortening the scan duration. METHODS: Twenty-eight STEMI patients underwent a CMR scan at 1.5 T, 3 ± 1 days following primary percutaneous coronary intervention. The AAR was quantified using both native T1 and T2-mapping. MI size was quantified using conventional LGE, post-contrast T1-mapping and synthetic magnitude-reconstructed inversion recovery (MagIR) LGE and synthetic phase-sensitive inversion recovery (PSIR) LGE, derived from the post-contrast T1 maps. RESULTS: Native T1-mapping performed as well as T2-mapping in delineating the AAR (41.6 ± 11.9% of the left ventricle [% LV] versus 41.7 ± 12.2% LV, P = 0.72; R2 0.97; ICC 0.986 (0.969-0.993); bias -0.1 ± 4.2% LV). There were excellent correlation and inter-method agreement with no bias, between MI size by conventional LGE, synthetic MagIR LGE (bias 0.2 ± 2.2%LV, P = 0.35), synthetic PSIR LGE (bias 0.4 ± 2.2% LV, P = 0.060) and post-contrast T1-mapping (bias 0.3 ± 1.8% LV, P = 0.10). The mean scan duration was 58 ± 4 min. Not performing T2 mapping (6 ± 1 min) and conventional LGE (10 ± 1 min) would shorten the CMR study by 15-20 min. CONCLUSIONS: T1-mapping can accurately quantify both the edema-based AAR (using native T1 maps) and acute MI size (using post-contrast T1 maps) in STEMI patients without major cardiovascular risk factors. This approach would shorten the duration of a comprehensive CMR study without significantly compromising on data acquisition and would obviate the need to perform T2 maps and LGE imaging.

Defining left ventricular remodeling following acute ST-segment elevation myocardial infarction using cardiovascular magnetic resonance.

BACKGROUND: The assessment of post-myocardial infarction (MI) left ventricular (LV) remodeling by cardiovascular magnetic resonance (CMR) currently uses criteria defined by echocardiography. Our aim was to provide CMR criteria for assessing LV remodeling following acute MI. METHODS: Firstly, 40 reperfused ST-segment elevation myocardial infarction (STEMI) patients with paired acute (4 ± 2 days) and follow-up (5 ± 2 months) CMR scans were analyzed by 2 independent reviewers and the minimal detectable changes (MDCs) for percentage change in LV end-diastolic volume (%ΔLVEDV), LV end-systolic volume (%ΔLVESV), and LV ejection fraction (%ΔLVEF) between the acute and follow-up scans were determined. Secondly, in 146 reperfused STEMI patients, receiver operator characteristic curve analyses for predicting LVEF <50% at follow-up (as a surrogate for clinical poor clinical outcome) were undertaken to obtain cut-off values for %ΔLVEDV and %ΔLVESV. RESULTS: The MDCs for %ΔLVEDV, %ΔLVESV, and %ΔLVEF were similar at 12%, 12%, 13%, respectively. The cut-off values for predicting LVEF < 50% at follow-up were 11% for %ΔLVEDV on receiver operating characteristic curve analysis (area under the curve (AUC) 0.75, 95% CI 0.6 to 0.83, sensitivity 72% specificity 70%), and 5% for %ΔLVESV (AUC 0.83, 95% CI 0.77 to 0.90, sensitivity and specificity 78%). Using cut-off MDC values (higher than the clinically important cut-off values) of 12% for both %ΔLVEDV and %ΔLVESV, 4 main patterns of LV remodeling were identified in our cohort: reverse LV remodeling (LVEF predominantly improved); no LV remodeling (LVEF predominantly unchanged); adverse LV remodeling with compensation (LVEF predominantly improved); and adverse LV remodeling (LVEF unchanged or worsened). CONCLUSIONS: The MDCs for %ΔLVEDV and %ΔLVESV between the acute and follow-up CMR scans of 12% each may be used to define adverse or reverse LV remodeling post-STEMI. The MDC for %ΔLVEF of 13%, relative to baseline, provides the minimal effect size required for investigating treatments aimed at improving LVEF following acute STEMI.

Diagnostic performance of T1 and T2 mapping to detect intramyocardial hemorrhage in reperfused ST-segment elevation myocardial infarction (STEMI) patients.

PURPOSE: To investigate the performance of T1 and T2 mapping to detect intramyocardial hemorrhage (IMH) in ST-segment elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention (PPCI). MATERIALS AND METHODS: Fifty STEMI patients were prospectively recruited between August 2013 and July 2014 following informed consent. Forty-eight patients completed a 1.5T cardiac magnetic resonance imaging (MRI) with native T1 , T2 , and T2* maps at 4 ± 2 days. Receiver operating characteristic (ROC) analyses were performed to assess the performance of T1 and T2 to detect IMH. RESULTS: The mean age was 59 ± 13 years old and 88% (24/48) were male. In all, 39 patients had interpretable T2* maps and 26/39 (67%) of the patients had IMH ( T2* <20 msec on T2* maps). Both T1 and T2 values of the hypointense core within the area-at-risk (AAR) performed equally well to detect IMH (T1 maps AUC 0.86 [95% confidence interval [CI] 0.72-0.99] versus T2 maps AUC 0.86 [95% CI 0.74-0.99]; P = 0.94). Using the binary assessment of presence or absence of a hypointense core on the maps, the diagnostic performance of T1 and T2 remained equally good (T1 AUC 0.87 [95% CI 0.73-1.00] versus T2 AUC 0.85 [95% CI 0.71-0.99]; P = 0.90) with good sensitivity and specificity (T1 : 88% and 85% and T2 : 85% and 85%, respectively). CONCLUSION: The presence of a hypointense core on the T1 and T2 maps can detect IMH equally well and with good sensitivity and specificity in reperfused STEMI patients and could be used as an alternative when T2* images are not acquired or are not interpretable. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:877-886.

Provision of magnetic resonance imaging for patients with 'MR-conditional' cardiac implantable electronic devices: an unmet clinical need.

AIMS: Increasing need for magnetic resonance imaging (MRI) has driven the development of MR-conditional cardiac implantable electronic devices (CIEDs; pacemakers and defibrillators); however, patients still report difficulties obtaining scans. We sought to establish current provision for MRI scanning of patients with CIEDs in England. METHODS AND RESULTS: A survey was distributed to all hospitals in England with MRI, to assess current practice. Information requested included whether hospitals currently offer MRI to this patient group, the number and type of scans acquired, local safety considerations, complications experienced and perceived obstacles to service provision in those departments not currently offering it. Responses were received from 195 of 227 (86%) of hospitals surveyed. Although 98% of departments were aware of MR-conditional devices, only 46% (n = 89) currently offer MRI scans to patients with CIED's; of these, 85% of departments perform ≤10 scans per year. No major complications were reported from MRI scanning in patients with MR-conditional devices. Current barriers to service expansion include perceived concerns regarding potential risk, lack of training, logistical difficulties, and lack of cardiology support. CONCLUSION: Provision of MRI for patients with CIEDs is currently poor, despite increasing numbers of patients with MR-conditional devices and extremely low reported complication rates.

Impact of microvascular obstruction on semiautomated techniques for quantifying acute and chronic myocardial infarction by cardiovascular magnetic resonance.

AIMS: The four most promising semiautomated techniques (5-SD, 6-SD, Otsu and the full width half maximum (FWHM)) were compared in paired acute and follow-up cardiovascular magnetic resonance (CMR), taking into account the impact of microvascular obstruction (MVO) and using automated extracellular volume fraction (ECV) maps for reference. Furthermore, their performances on the acute scan were compared against manual myocardial infarct (MI) size to predict adverse left ventricular (LV) remodelling (≥20% increase in end-diastolic volume). METHODS: 40 patients with reperfused ST segment elevation myocardial infarction (STEMI) with a paired acute (4±2 days) and follow-up CMR scan (5±2 months) were recruited prospectively. All CMR analysis was performed on CVI42. RESULTS: Using manual MI size as the reference standard, 6-SD accurately quantified acute (24.9±14.0%LV, p=0.81, no bias) and chronic MI size (17.2±9.7%LV, p=0.88, no bias). The performance of FWHM for acute MI size was affected by the acquisition sequence used. Furthermore, FWHM underestimated chronic MI size in those with previous MVO due to the significantly higher ECV in the MI core on the follow-up scans previously occupied by MVO (82 (75-88)% vs 62 (51-68)%, p<0.001). 5-SD and Otsu were precise but overestimated acute and chronic MI size. All techniques were performed with high diagnostic accuracy and equally well to predict adverse LV remodelling. CONCLUSIONS: 6-SD was the most accurate for acute and chronic MI size and should be the preferred semiautomatic technique in randomised controlled trials. However, 5-SD, FWHM and Otsu could also be used when precise MI size quantification may be adequate (eg, observational studies).

Residual Myocardial Iron Following Intramyocardial Hemorrhage During the Convalescent Phase of Reperfused ST-Segment-Elevation Myocardial Infarction and Adverse Left Ventricular Remodeling.

BACKGROUND: The presence of intramyocardial hemorrhage (IMH) in ST-segment-elevation myocardial infarction patients reperfused by primary percutaneous coronary intervention has been associated with residual myocardial iron at follow-up, and its impact on adverse left ventricular (LV) remodeling is incompletely understood and is investigated here. METHODS AND RESULTS: Forty-eight ST-segment-elevation myocardial infarction patients underwent cardiovascular magnetic resonance at 4±2 days post primary percutaneous coronary intervention, of whom 40 had a follow-up scan at 5±2 months. Native T1, T2, and T2* maps were acquired. Eight out of 40 (20%) patients developed adverse LV remodeling. A subset of 28 patients had matching T2* maps, of which 15/28 patients (54%) had IMH. Eighteen of 28 (64%) patients had microvascular obstruction on the acute scan, of whom 15/18 (83%) patients had microvascular obstruction with IMH. On the follow-up scan, 13/15 patients (87%) had evidence of residual iron within the infarct zone. Patients with residual iron had higher T2 in the infarct zone surrounding the residual iron when compared with those without. In patients with adverse LV remodeling, T2 in the infarct zone surrounding the residual iron was also higher than in those without (60 [54-64] ms versus 53 [51-56] ms; P=0.025). Acute myocardial infarct size, extent of microvascular obstruction, and IMH correlated with the change in LV end-diastolic volume (Pearson's rho of 0.64, 0.59, and 0.66, respectively; P=0.18 and 0.62, respectively, for correlation coefficient comparison) and performed equally well on receiver operating characteristic curve for predicting adverse LV remodeling (area under the curve: 0.99, 0.94, and 0.95, respectively; P=0.19 for receiver operating characteristic curve comparison). CONCLUSIONS: The majority of ST-segment-elevation myocardial infarction patients with IMH had residual myocardial iron at follow-up. This was associated with persistently elevated T2 values in the surrounding infarct tissue and adverse LV remodeling. IMH and residual myocardial iron may be potential therapeutic targets for preventing adverse LV remodeling in reperfused ST-segment-elevation myocardial infarction patients.

Automated Extracellular Volume Fraction Mapping Provides Insights Into the Pathophysiology of Left Ventricular Remodeling Post-Reperfused ST-Elevation Myocardial Infarction.

BACKGROUND: Whether the remote myocardium of reperfused ST-segment elevation myocardial infarction (STEMI) patients plays a part in adverse left ventricular (LV) remodeling remains unclear. We aimed to use automated extracellular volume fraction (ECV) mapping to investigate whether changes in the ECV of the remote (ECVR emote) and infarcted myocardium (ECVI nfarct) impacted LV remodeling. METHODS AND RESULTS: Forty-eight of 50 prospectively recruited reperfused STEMI patients completed a cardiovascular magnetic resonance at 4±2 days and 40 had a follow-up scan at 5±2 months. Twenty healthy volunteers served as controls. Mean segmental values for native T1, T2, and ECV were obtained. Adverse LV remodeling was defined as ≥20% increase in LV end-diastolic volume. ECVR emote was higher on the acute scan when compared to control (27.9±2.1% vs 26.4±2.1%; P=0.01). Eight patients developed adverse LV remodeling and had higher ECVR emote acutely (29.5±1.4% vs 27.4±2.0%; P=0.01) and remained higher at follow-up (28.6±1.5% vs 26.6±2.1%; P=0.02) compared to those without. Patients with a higher ECVR emote and a lower myocardial salvage index (MSI) acutely were significantly associated with adverse LV remodeling, independent of T1Remote, T1Core and microvascular obstruction, whereas a higher ECVI nfarct was significantly associated with worse wall motion recovery. CONCLUSIONS: ECVR emote was increased acutely in reperfused STEMI patients. Those with adverse LV remodeling had higher ECVR emote acutely, and this remained higher at follow-up than those without adverse LV remodeling. A higher ECVR emote and a lower MSI acutely were significantly associated with adverse LV remodeling whereas segments with higher ECVI nfarct were less likely to recover wall motion.