Elevated serum uric acid affects myocardial reperfusion and infarct size in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

AIMS

Elevated serum uric acid (eSUA) was associated with unfavorable outcome in patients with ST-segment elevation myocardial infarction (STEMI). However, the effect of eSUA on myocardial reperfusion injury and infarct size has been poorly investigated. Our aim was to correlate eSUA with infarct size, infarct size shrinkage, myocardial reperfusion grade and long-term mortality in STEMI patients undergoing primary percutaneous coronary intervention.

METHODS

We performed a post-hoc patients-level analysis of two randomized controlled trials, testing strategies for myocardial ischemia/reperfusion injury protection. Each patient underwent acute (3-5 days) and follow-up (4-6 months) cardiac magnetic resonance. Infarct size and infarct size shrinkage were outcomes of interest. We assessed T2-weighted edema, myocardial blush grade (MBG), corrected Thrombolysis in myocardial infarction Frame Count, ST-segment resolution and long-term all-cause mortality.

RESULTS

A total of 101 (86.1% anterior) STEMI patients were included; eSUA was found in 16 (15.8%) patients. Infarct size was larger in eSUA compared with non-eSUA patients (42.3 ± 22 vs. 29.1 ± 15 ml, P = 0.008). After adjusting for covariates, infarct size was 10.3 ml (95% confidence interval 1.2-19.3 ml, P = 0.001) larger in eSUA. Among patients with anterior myocardial infarction the difference in delayed enhancement between groups was maintained (respectively, 42.3 ± 22.4 vs. 29.9 ± 15.4 ml, P = 0.015). Infarct size shrinkage was similar between the groups. Compared with non-eSUA, eSUA patients had larger T2-weighted edema (53.8 vs. 41.2 ml, P = 0.031) and less favorable MBG (MBG < 2: 44.4 vs. 13.6%, P = 0.045). Corrected Thrombolysis in myocardial infarction Frame Count and ST-segment resolution did not significantly differ between the groups. At a median follow-up of 7.3 years, all-cause mortality was higher in the eSUA group (18.8 vs. 2.4%, P = 0.028).

CONCLUSION

eSUA may affect myocardial reperfusion in patients with STEMI undergoing percutaneous coronary intervention and is associated with larger infarct size and higher long-term mortality.

Cardiac magnetic resonance for ischaemia and viability detection. Guiding patient selection to revascularization in coronary chronic total occlusions: The CARISMA_CTO study design

BACKGROUND

It is debated whether percutaneous revascularization (PCI) of total coronary chronic occlusion (CTO) is superior to optimal medical therapy (OMT) in improving symptoms, left ventricular (LV) function and major adverse cardiac/cerebrovascular events (MACCE). Furthermore, CTO-PCI is a challenging technique, with lower success rate than in other settings. A systematic analysis of baseline LV function, infarction extent and ischaemic burden to predict response to revascularization has never been performed.

PURPOSES

To establish a CMR protocol to identify patients (pts) who can benefit most from CTO-PCI. Myocardial viability/ischaemia retains high biological plausibility as predictors of response to revascularization. Therefore, baseline viability (necrotic tissue extent, response to inotropic stimulation) and ischaemia (perfusion defect, wall motion abnormality during stress) will be studied as potential predictors of mechanical LV segmental improvement and ischaemic burden reduction in CTO territory (primary endpoint), LV remodelling and global function, Seattle Angina Questionnaire, and MACCE improvement (secondary endpoints) in the follow-up.

METHODS

Pts with CTO suitable for PCI undergo stress-CMR for viability/ischaemia assessment. Pts with normal LV function undergo adenosine, those with moderately-reduced ejection fraction (EF) and wall motion abnormalities high-dose dobutamine, pts with EF <35% low-dose dobutamine. All pts undergo late gadolinium enhancement and repeat the same scan at 12 ± 3 months, regardless of PCI success or decision for OMT.

CONCLUSIONS

A multi-parameter CMR protocol tailored on pts characteristics to study viability/ischaemia could help in identifying responders in terms of LV function, ischaemic burden and clinical outcome among pts suitable for CTO-PCI, improving selection of best candidates to percutaneous revascularization.

Persistent abnormalities in pulmonary arterial compliance after heart transplantation in patients with combined post-capillary and pre-capillary pulmonary hypertension

Background

The hemodynamic definitions of pulmonary hypertension (PH) in left heart disease have recently been refined to better match the characteristics required to reflect the presence of pulmonary vascular disease. Accordingly, we tested the hypothesis that abnormalities in the stiffness of pulmonary circulation would persist after heart transplantation in patients with combined post-capillary and pre-capillary PH (Cpc-PH) in contrast to those with isolated post-capillary PH (Ipc-PH).

Methods

We retrospectively analyzed right heart hemodynamics in a cohort of 295 consecutive patients with heart failure and advanced left ventricular systolic dysfunction (LVSD) before and 1 year after heart transplantation.

Results

According to their baseline hemodynamic profile, patients were classified as: 75 Cpc-PH, 111 Ipc-PH, and 98 without PH (no-PH), and 11 pre-capillary PH. One year after heart transplantation, pulmonary artery pressures, pulmonary vascular resistance and cardiac index normalized in all patients regardless of the baseline hemodynamic profile. However, pulmonary arterial compliance remained lower in Cpc-PH patients (from 1.6±1.2 at baseline to 3.7±1.4 ml/mmHg at 1 year) than in Ipc-PH (from 1.2±2.0 to 4.4±2.3 ml/mmHg) and no-PH patients (from 3.7±2.0 to 4.5±1.8 ml/mmHg); (adjusted p = 0.03 Ipc-PH vs. Cpc-PH _INT<0.001).

Conclusions

In heart failure patients with advanced LVSD, a hemodynamic profile characterized by Cpc-PH predicts the persistence of a stiffer pulmonary circulation at 1 year after heart transplantation.

Prognostic Stratification of Patients With ST-Segment-Elevation Myocardial Infarction (PROSPECT): A Cardiac Magnetic Resonance Study

BACKGROUND

Cardiac magnetic resonance (CMR) is a robust tool to evaluate left ventricular ejection fraction (LVEF), myocardial salvage index, microvascular obstruction, and myocardial hemorrhage in patients with ST-segment-elevation myocardial infarction. We evaluated the additional prognostic benefit of a CMR score over standard prognostic stratification with global registry of acute coronary events (GRACE) score and transthoracic echocardiography LVEF measurement.

METHODS AND RESULTS

Two hundred nine consecutive patients with ST-segment-elevation myocardial infarction (age, 61.4±11.4 years; 162 men) underwent transthoracic echocardiography and CMR after succesful primary percutaneous coronary intervention. Major adverse cardiac events (MACE) were assessed at a mean follow-up of 2.5±1.2 years. MACE occurred in 24 (12%) patients who at baseline showed higher GRACE risk score (P<0.01), lower LVEF with both transthoracic echocardiography and CMR, lower myocardial salvage index, and higher per-patient myocardial hemorrhage and microvascular obstruction prevalence and amount as compared with patients without MACE (P<0.01). The best cut-off values of transthoracic echocardiography-LVEF, CMR-LVEF, myocardial salvage index, and microvascular obstruction to predict MACE were 46.7%, 37.5%, 0.4, and 2.6% of left ventricular mass, respectively. Accordingly, a weighted CMR score, including the following 4 variables (CMR-LVEF, myocardial salvage index, microvascular obstruction, and myocardial hemorrhage), with a maximum of 17 points was calculated and included in the multivariable analysis showing that only CMR score (hazard ratio, 1.867 per SD increase [1.311-2.658]; P<0.001) was independently associated with MACE with the highest net reclassification improvement as compared to GRACE score and transthoracic echocardiography-LVEF measurement.

CONCLUSIONS

CMR score provides incremental prognostic stratification as compared with GRACE score and transthoracic echocardiography-LVEF and may impact the management of patients with ST-segment-elevation myocardial infarction.

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.

Circadian variation in acute myocardial infarct size assessed by cardiovascular magnetic resonance in reperfused STEMI patients

OBJECTIVE

Clinical studies using serum cardiac biomarkers to investigate a circadian variation in acute myocardial infarct (MI) size in ST-segment elevation myocardial infarction (STEMI) patients reperfused by primary percutaneous coronary intervention (PPCI) have produced mixed results. We aimed to investigate this phenomenon using acute MI size measured by cardiovascular magnetic resonance (CMR).

METHODS

Patient-level data was obtained from 4 randomized controlled trials investigating the MI-limiting effects of cardioprotective therapies in this pooled analysis. The primary analysis was performed in those patients with no pre-infarct angina; duration of ischemia >60min and <360min; Thrombolysis In Myocardial Infarction (TIMI) flow pre-PPCI ≤1; TIMI flow post-PPCI 3; and no collateral flow.

RESULTS

169 out of 376 patients with CMR data met the inclusion criteria for the primary analysis. A 24-hour circadian variation in acute MI size as a % of the area-at-risk (%AAR), after adjusting for confounders, was observed with a peak and nadir MI size in patients with symptom onset between 00:00 and 01:00 and between 12:00 and 13:00 respectively (difference from the average MI size 5.2%, 95%CI 1.1-9.4%; p=0.013). This was associated with a non-significant circadian variation in left ventricular ejection fraction (LVEF) (difference from the average LVEF 5.9%, 95%CI -0.6-2.2%, p=0.073). There was no circadian variation in MI size or LVEF in the whole cohort.

CONCLUSIONS

We report a circadian variation in acute MI size assessed by CMR in a subset of STEMI patients treated by PPCI, with the largest and smallest MI size occurring in patients with symptom onset between 00:00 and 01:00 and between 12:00 and 13:00 respectively.

Prognostic value of TAPSE after therapy optimisation in patients with pulmonary arterial hypertension is independent of the haemodynamic effects of therapy

Objective

To evaluate the prognostic significance of right ventricular function assessed by echocardiography after start or escalation of targeted therapy in patients with pulmonary arterial hypertension.

Methods

Study design: longitudinal study. Setting: tertiary referral centre for pulmonary hypertension. Patients: 81 consecutive patients with pulmonary arterial hypertension (33 naive and 48 prevalent). Interventions: right heart catheterisation and echocardiography performed prior to starting or escalating targeted therapy and repeated in 55 patients after 4–12 months of therapy. Main outcome measure: survival after follow-up examinations.

Results

11 patients died and 7 were lost to follow-up during the first year; 8 patients underwent first follow-up evaluation beyond 1 year. 55 patients were re-evaluated after therapy; during the subsequent follow-up period of 25 months, 9 patients died, 7 worsened from WHO I/II to III/IV and 15 remained in WHO III/IV despite therapy. A baseline tricuspid annular plane systolic excursion (TAPSE) ≥15 mm was associated with a lower risk of death (HR=0.32; 95% CI 0.12 to 0.83, p=0.012). Attaining a TAPSE≥15 mm after therapy was associated with a significantly lower risk of death or clinical worsening (HR=0.2; 95% CI 0.1 to 0.6, p=0.002) and a lower risk of death which approached statistical significance (HR=0.3; 95% CI 0.2 to 1.1, p=0.075). Per cent changes in TAPSE were loosely related to changes in pulmonary vascular resistances after therapy (R=0.37).

Conclusions

In patients with pulmonary arterial hypertension, the evaluation of right ventricular function by TAPSE after targeted therapy is useful to predict subsequent prognosis, regardless of the haemodynamic effects of therapy.

Pulmonary arterial compliance: How and why should we measure it?

The pulmonary circulation is a high-flow/low-pressure system, coupled with a flow generator chamber-the right ventricle-, which is relatively unable to tolerate increases in afterload. A right heart catheterization, using a fluid-filled, balloon-tipped Swan-Ganz catheter allows the measurement of all hemodynamic parameters characterizing the pulmonary circulation: the inflow pressure, an acceptable estimate the outflow pressure, and the pulmonary blood flow. However, the study of the pulmonary circulation as a continuous flow system is an oversimplification and a thorough evaluation of the pulmonary circulation requires a correct understanding of the load that the pulmonary vascular bed imposes on the right ventricle, which includes static and dynamic components. This is critical to assess the prognosis of patients with pulmonary hypertension or with heart failure. Pulmonary compliance is a measure of arterial distensibility and, either alone or in combination with pulmonary vascular resistance, gives clinicians the possibility of a good prognostic stratification of patients with heart failure or with pulmonary hypertension. The measurement of pulmonary arterial compliance should be included in the routine clinical evaluation of such patients.

Prognostic Value of Late Gadolinium Enhancement Cardiovascular Magnetic Resonance in Cardiac Amyloidosis

Supplemental Digital Content is available in the text.

The prognosis and treatment of the 2 main types of cardiac amyloidosis, immunoglobulin light chain (AL) and transthyretin (ATTR) amyloidosis, are substantially influenced by cardiac involvement. Cardiovascular magnetic resonance with late gadolinium enhancement (LGE) is a reference standard for the diagnosis of cardiac amyloidosis, but its potential for stratifying risk is unknown.

[Mutation of the lamin A/C gene associated with left ventricular apical hypoplasia: a new phenotype for laminopathies?]

Isolated left ventricular (LV) apical hypoplasia is a rare anomaly characterized by a dysfunctioning, spherical left ventricle and elongated right ventricle wrapping around the deficient LV apex. The etiology is unknown; it is presumed to be a rare congenital developmental defect during partitioning of the ventricles, caused by an in-utero infection. We describe for the first time a case of isolated LV apical hypoplasia associated with lamin A/C gene mutation. Echocardiography showed a mildly dilated left ventricle with spherical configuration and impaired systolic function, and an elongated right ventricle wrapping around the deficient LV apex. Magnetic resonance imaging also identified fatty replacement of the LV apical myocardium. Late gadolinium enhancement imaging showed mid-wall fibrosis in the interventricular septum. Family screening by ECG and echocardiography failed to identify heart disease in the patient's family; however, the proband's father and daughter were found to carry the same mutation. This case report highlights the difficulties of a correct interpretation of genetic mutations in a single patient with cardiomyopathy. Indeed, the causative role of a mutation needs to be confirmed by co-segregation analysis. Although the etiology of LV apical hypoplasia remains unknown, the first hypothesis is an acquired process interfering with the early development of the heart, the new one is a genetic defect.

Reproducibility of native myocardial T1 mapping in the assessment of Fabry disease and its role in early detection of cardiac involvement by cardiovascular magnetic resonance

BACKGROUND

Cardiovascular magnetic resonance (CMR) derived native myocardial T1 is decreased in patients with Fabry disease even before left ventricular hypertrophy (LVH) occurs and may be the first non-invasive measure of myocyte sphingolipid storage. The relationship of native T1 lowering prior to hypertrophy and other candidate early phenotype markers are unknown. Furthermore, the reproducibility of T1 mapping has never been assessed in Fabry disease.

METHODS

Sixty-three patients, 34 (54%) female, mean age 48±15 years with confirmed (genotyped) Fabry disease underwent CMR, ECG and echocardiographic assessment. LVH was absent in 25 (40%) patients. Native T1 mapping was performed with both Modified Look-Locker Inversion recovery (MOLLI) sequences and a shortened version (ShMOLLI) at 1.5 Tesla. Twenty-one patients underwent a second scan within 24 hours to assess inter-study reproducibility. Results were compared with 63 healthy age and gender-matched volunteers.

RESULTS

Mean native T1 in Fabry disease (LVH positive), (LVH negative) and healthy volunteers was 853±50 ms, 904±46 ms and 968±32 ms (for all p<0.0001) by ShMOLLI sequences. Native T1 showed high inter-study, intra-observer and inter-observer agreement with intra-class correlation coefficients (ICC) of 0.99, 0.98, 0.97 (ShMOLLI) and 0.98, 0.98, 0.98 (MOLLI). In Fabry disease LVH negative individuals, low native T1 was associated with reduced echocardiographic-based global longitudinal speckle tracking strain (-18±2% vs -22±2%, p=0.001) and early diastolic function impairment (E/E'=7 [6-8] vs 5 [5-6], p=0.028).

CONCLUSION

Native T1 mapping in Fabry disease is a reproducible technique. T1 reduction prior to the onset of LVH is associated with early diastolic and systolic changes measured by echocardiography.

Remote ischemic post-conditioning of the lower limb during primary percutaneous coronary intervention safely reduces enzymatic infarct size in anterior myocardial infarction: a randomized controlled trial

OBJECTIVES

This study sought to evaluate whether remote ischemic post-conditioning (RIPC) could reduce enzymatic infarct size in patients with anterior ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (pPCI).

BACKGROUND

Myocardial reperfusion injury may attenuate the benefit of pPCI. In animal models, RIPC mitigates myocardial reperfusion injury.

METHODS

One hundred patients with anterior ST-segment elevation myocardial infarction and occluded left anterior descending artery were randomized to pPCI + RIPC (n = 50) or conventional pPCI (n = 50). RIPC consisted of 3 cycles of 5 min/5 min ischemia/reperfusion by cuff inflation/deflation of the lower limb. The primary endpoint was infarct size assessed by the area under the curve of creatinine kinase-myocardial band release (CK-MB). Secondary endpoints included the following: infarct size assessed by cardiac magnetic resonance delayed enhancement volume; T2-weighted edema volume; ST-segment resolution >50%; TIMI (Thrombolysis In Myocardial Infarction) frame count; and myocardial blush grading.

RESULTS

Four patients (2 RIPC, 2 controls) were excluded due to missing samples of CK-MB. A total of 96 patients were analyzed; median area under the curve CK-MB was 8,814 (interquartile range [IQR]: 5,567 to 11,325) arbitrary units in the RIPC group and 10,065 (IQR: 7,465 to 14,004) arbitrary units in control subjects (relative reduction: 20%, 95% confidence interval: 0.2% to 28.7%; p = 0.043). Seventy-seven patients underwent a cardiac magnetic resonance scan 3 to 5 days after randomization, and 66 patients repeated a second scan after 4 months. T2-weighted edema volume was 37 ± 16 cc in RIPC patients and 47 ± 22 cc in control subjects (p = 0.049). ST-segment resolution >50% was 66% in RIPC and 37% in control subjects (p = 0.015). We observed no significant differences in TIMI frame count, myocardial blush grading, and delayed enhancement volume.

CONCLUSIONS

In patients with anterior ST-segment elevation myocardial infarction, RIPC at the time of pPCI reduced enzymatic infarct size and was also associated with an improvement of T2-weighted edema volume and ST-segment resolution >50%. (Remote Postconditioning in Patients With Acute Myocardial Infarction Treated by Primary Percutaneous Coronary Intervention [PCI] [RemPostCon]; NCT00865722).

Analyses of longitudinal and of transverse right ventricular function provide different clinical information in patients with pulmonary hypertension

We tested the hypothesis that analysis of longitudinal right ventricular (RV) function and analysis of transverse RV function by echocardiography provide different clinical information in patients with pulmonary hypertension (PH). Indices of longitudinal and transverse RV function were obtained with different echocardiographic techniques in 30 patients with idiopathic pulmonary arterial hypertension, 28 patients with systolic left ventricular dysfunction and PH (sLVD PH), 27 patients with sLVD and normal pulmonary pressure (sLVD no PH) undergoing right heart catheterization and 20 healthy patients. Indices of RV transverse function were significantly worse in patients with PH than in patients without PH and did not statistically differ between patients with normal and those with reduced cardiac index; RV diameter shortening at mid-segment correlated best with mean pulmonary artery pressure (h = 0.63, p < 0.001). Indices of longitudinal function were poorly related to severity of PH, but a tricuspid annular plane systolic excursion <15 mm predicted a cardiac index <2.5 L/min/m(2) with 80% sensitivity and 93% specificity (area under curve = 0.85). In conclusion, in patients with PH, reduced transverse RV function is a reliable indicator of the presence of high pulmonary artery pressure, whereas reduced RV longitudinal function is associated with impairment of cardiac function.