Prevalence of Coronary Artery Disease and Coronary Microvascular Dysfunction in Patients With Heart Failure With Preserved Ejection Fraction

Importance

Coronary artery disease (CAD) and coronary microvascular dysfunction (CMD) may contribute to the pathophysiologic characteristics of heart failure with preserved ejection fraction (HFpEF). However, the prevalence of CAD and CMD have not been systematically studied.

Objective

To examine the prevalence of CAD and CMD in hospitalized patients with HFpEF.

Design, Setting, and Participants

A total of 106 consecutive patients hospitalized with HFpEF were evaluated in this prospective, multicenter, cohort study conducted between January 2, 2017, and August 1, 2018; data analysis was performed from March 4 to September 6, 2019. Participants underwent coronary angiography with guidewire-based assessment of coronary flow reserve, index of microvascular resistance, and fractional flow reserve, followed by coronary vasoreactivity testing. Cardiac magnetic resonance imaging was performed with late gadolinium enhancement and assessment of extracellular volume. Myocardial perfusion was assessed qualitatively and semiquantitatively using the myocardial-perfusion reserve index.

Main Outcomes and Measures

The prevalence of obstructive epicardial CAD, CMD, and myocardial ischemia, infarction, and fibrosis.

Results

Of 106 participants enrolled (53 [50%] women; mean [SD] age, 72 [9] years), 75 had coronary angiography, 62 had assessment of coronary microvascular function, 41 underwent coronary vasoreactivity testing, and 52 received cardiac magnetic resonance imaging. Obstructive epicardial CAD was present in 38 of 75 participants (51%, 95% CI, 39%-62%); 19 of 38 (50%; 95% CI, 34%-66%) had no history of CAD. Endothelium-independent CMD (ie, coronary flow reserve <2.0 and/or index of microvascular resistance ≥25) was identified in 41 of 62 participants (66%; 95% CI, 53%-77%). Endothelium-dependent CMD (ie, abnormal coronary vasoreactivity) was identified in 10 of 41 participants (24%; 95% CI, 13%-40%). Overall, 45 of 53 participants (85%; 95% CI, 72%-92%) had evidence of CMD and 29 of 36 (81%; 95% CI, 64%-91%) of those without obstructive epicardial CAD had CMD. Cardiac magnetic resonance imaging findings included myocardial-perfusion reserve index less than or equal to 1.84 (ie, impaired global myocardial perfusion) in 29 of 41 patients (71%; 95% CI, 54%-83%), visual perfusion defect in 14 of 46 patients (30%; 95% CI, 19%-46%), ischemic late gadolinium enhancement (ie, myocardial infarction) in 14 of 52 patients (27%; 95% CI, 16%-41%), and extracellular volume greater than 30% (ie, diffuse myocardial fibrosis) in 20 of 48 patients (42%; 95% CI, 28%-56%). Patients with obstructive CAD had more adverse events during follow-up (28 [74%]) than those without obstructive CAD (17 [46%]).

Conclusions and Relevance

In this cohort study, 91% of patients with HFpEF had evidence of epicardial CAD, CMD, or both. Of those without obstructive CAD, 81% had CMD. Obstructive epicardial CAD and CMD appear to be common and often unrecognized in hospitalized patients with HFpEF and may be therapeutic targets.

Percutaneous coronary angioplasty versus coronary artery bypass grafting in the treatment of unprotected left main stenosis: updated 5-year outcomes from the randomised, non-inferiority NOBLE trial

BACKGROUND

Percutaneous coronary intervention (PCI) is increasingly used in revascularisation of patients with left main coronary artery disease in place of the standard treatment, coronary artery bypass grafting (CABG). The NOBLE trial aimed to evaluate whether PCI was non-inferior to CABG in the treatment of left main coronary artery disease and reported outcomes after a median follow-up of 3·1 years. We now report updated 5-year outcomes of the trial.

METHODS

The prospective, randomised, open-label, non-inferiority NOBLE trial was done at 36 hospitals in nine northern European countries. Patients with left main coronary artery disease requiring revascularisation were enrolled and randomly assigned (1:1) to receive PCI or CABG. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), a composite of all-cause mortality, non-procedural myocardial infarction, repeat revascularisation, and stroke. Non-inferiority of PCI to CABG was defined as the upper limit of the 95% CI of the hazard ratio (HR) not exceeding 1·35 after 275 MACCE had occurred. Secondary endpoints included all-cause mortality, non-procedural myocardial infarction, and repeat revascularisation. Outcomes were analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT01496651.

FINDINGS

Between Dec 9, 2008, and Jan 21, 2015, 1201 patients were enrolled and allocated to PCI (n=598) or CABG (n=603), with 17 subsequently lost to early follow-up. 592 patients in each group were included in this analysis. At a median of 4·9 years of follow-up, the predefined number of events was reached for adequate power to assess the primary endpoint. Kaplan-Meier 5-year estimates of MACCE were 28% (165 events) for PCI and 19% (110 events) for CABG (HR 1·58 [95% CI 1·24-2·01]); the HR exceeded the limit for non-inferiority of PCI compared to CABG. CABG was found to be superior to PCI for the primary composite endpoint (p=0·0002). All-cause mortality was estimated in 9% after PCI versus 9% after CABG (HR 1·08 [95% CI 0·74-1·59]; p=0·68); non-procedural myocardial infarction was estimated in 8% after PCI versus 3% after CABG (HR 2·99 [95% CI 1·66-5·39]; p=0·0002); and repeat revascularisation was estimated in 17% after PCI versus 10% after CABG (HR 1·73 [95% CI 1·25-2·40]; p=0·0009).

INTERPRETATION

In revascularisation of left main coronary artery disease, PCI was associated with an inferior clinical outcome at 5 years compared with CABG. Mortality was similar after the two procedures but patients treated with PCI had higher rates of non-procedural myocardial infarction and repeat revascularisation.

FUNDING

Biosensors.

Neurocardiogenic syncope precipitated by digoxin

We present a 72-year-old man with worsening cardiac failure, atrial fibrillation and recurrent syncope precipitated by the prescription of digoxin. Neurocardiogenic syncope was diagnosed however the patient died prior to definitive treatment. Post-mortem revealed primary amyloid as the unifying diagnosis.

Myocardial Hemorrhage After Acute Reperfused ST-Segment-Elevation Myocardial Infarction: Relation to Microvascular Obstruction and Prognostic Significance

Supplemental Digital Content is available in the text.

Background—

The success of coronary reperfusion therapy in ST-segment–elevation myocardial infarction (MI) is commonly limited by failure to restore microvascular perfusion.

Methods and Results—

We performed a prospective cohort study in patients with reperfused ST-segment–elevation MI who underwent cardiac magnetic resonance 2 days (n=286) and 6 months (n=228) post MI. A serial imaging time-course study was also performed (n=30 participants; 4 cardiac magnetic resonance scans): 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. Myocardial hemorrhage was taken to represent a hypointense infarct core with a T2* value of <20 ms. Microvascular obstruction was assessed with late gadolinium enhancement. Adverse remodeling was defined as an increase in left ventricular end-diastolic volume ≥20% at 6 months. Cardiovascular death or heart failure events post discharge were assessed during follow-up. Two hundred forty-five patients had evaluable T2* data (mean±age, 58 [11] years; 76% men). Myocardial hemorrhage 2 days post MI was associated with clinical characteristics indicative of MI severity and inflammation. Myocardial hemorrhage was a multivariable associate of adverse remodeling (odds ratio [95% confidence interval]: 2.64 [1.07–6.49]; P=0.035). Ten (4%) patients had a cardiovascular cause of death or experienced a heart failure event post discharge, and myocardial hemorrhage, but not microvascular obstruction, was associated with this composite adverse outcome (hazard ratio, 5.89; 95% confidence interval, 1.25–27.74; P=0.025), including after adjustment for baseline left ventricular end-diastolic volume. In the serial imaging time-course study, myocardial hemorrhage occurred in 7 (23%), 13 (43%), 11 (33%), and 4 (13%) patients 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. The amount of hemorrhage (median [interquartile range], 7.0 [4.9–7.5]; % left ventricular mass) peaked on day 2 (P<0.001), whereas microvascular obstruction decreased with time post reperfusion.

Conclusions—

Myocardial hemorrhage and microvascular obstruction follow distinct time courses post ST-segment–elevation MI. Myocardial hemorrhage was more closely associated with adverse outcomes than microvascular obstruction.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02072850.

Temporal Evolution of Myocardial Hemorrhage and Edema in Patients After Acute ST-Segment Elevation Myocardial Infarction: Pathophysiological Insights and Clinical Implications

Background

The time course and relationships of myocardial hemorrhage and edema in patients after acute ST‐segment elevation myocardial infarction (STEMI) are uncertain.

Methods and Results

Patients with ST‐segment elevation myocardial infarction treated by primary percutaneous coronary intervention underwent cardiac magnetic resonance imaging on 4 occasions: at 4 to 12 hours, 3 days, 10 days, and 7 months after reperfusion. Myocardial edema (native T2) and hemorrhage (T2*) were measured in regions of interest in remote and injured myocardium. Myocardial hemorrhage was taken to represent a hypointense infarct core with a T2* value <20 ms. Thirty patients with ST‐segment elevation myocardial infarction (mean age 54 years; 25 [83%] male) gave informed consent. Myocardial hemorrhage occurred in 7 (23%), 13 (43%), 11 (33%), and 4 (13%) patients at 4 to 12 hours, 3 days, 10 days, and 7 months, respectively, consistent with a unimodal pattern. The corresponding median amounts of myocardial hemorrhage (percentage of left ventricular mass) during the first 10 days after myocardial infarction were 2.7% (interquartile range [IQR] 0.0–5.6%), 7.0% (IQR 4.9–7.5%), and 4.1% (IQR 2.6–5.5%; P<0.001). Similar unimodal temporal patterns were observed for myocardial edema (percentage of left ventricular mass) in all patients (P=0.001) and for infarct zone edema (T2, in ms: 62.1 [SD 2.9], 64.4 [SD 4.9], 65.9 [SD 5.3]; P<0.001) in patients without myocardial hemorrhage. Alternatively, in patients with myocardial hemorrhage, infarct zone edema was reduced at day 3 (T2, in ms: 51.8 [SD 4.6]; P<0.001), depicting a bimodal pattern. Left ventricular end‐diastolic volume increased from baseline to 7 months in patients with myocardial hemorrhage (P=0.001) but not in patients without hemorrhage (P=0.377).

Conclusions

The temporal evolutions of myocardial hemorrhage and edema are unimodal, whereas infarct zone edema (T2 value) has a bimodal pattern. Myocardial hemorrhage is prognostically important and represents a target for therapeutic interventions that are designed to preserve vascular integrity following coronary reperfusion.

Clinical Trial Registration

URL: https://clinicaltrials.gov/. Unique identifier: NCT02072850.

Microvascular Resistance Predicts Myocardial Salvage and Infarct Characteristics in ST-Elevation Myocardial Infarction

BACKGROUND

The pathophysiology of myocardial injury and repair in patients with ST-elevation myocardial infarction is incompletely understood. We investigated the relationships among culprit artery microvascular resistance, myocardial salvage, and ventricular function.

METHODS AND RESULTS

The index of microvascular resistance (IMR) was measured by means of a pressure- and temperature-sensitive coronary guidewire in 108 patients with ST-elevation myocardial infarction (83% male) at the end of primary percutaneous coronary intervention. Paired cardiac MRI (cardiac magnetic resonance) scans were performed early (2 days; n=108) and late (3 months; n=96) after myocardial infarction. T(2)-weighted- and late gadolinium-enhanced cardiac magnetic resonance delineated the ischemic area at risk and infarct size, respectively. Myocardial salvage was calculated by subtracting infarct size from area at risk. Univariable and multivariable models were constructed to determine the impact of IMR on cardiac magnetic resonance-derived surrogate outcomes. The median (interquartile range) IMR was 28 (17-42) mm Hg/s. The median (interquartile range) area at risk was 32% (24%-41%) of left ventricular mass, and the myocardial salvage index was 21% (11%-43%). IMR was a significant multivariable predictor of early myocardial salvage, with a multiplicative effect of 0.87 (95% confidence interval 0.82 to 0.92) per 20% increase in IMR; P<0.001. In patients with anterior myocardial infarction, IMR was a multivariable predictor of early and late myocardial salvage, with multiplicative effects of 0.82 (95% confidence interval 0.75 to 0.90; P<0.001) and 0.92 (95% confidence interval 0.88 to 0.96; P<0.001), respectively. IMR also predicted the presence and extent of microvascular obstruction and myocardial hemorrhage.

CONCLUSION

Microvascular resistance measured during primary percutaneous coronary intervention significantly predicts myocardial salvage, infarct characteristics, and left ventricular ejection fraction in patients with ST-elevation myocardial infarction. (J Am Heart Assoc. 2012;1:e002246 doi: 10.1161/JAHA.112.002246).

An unusual complication of transradial coronary angiography

We report the first case of extensive cellulitis and staphylococcal bacteremia with the subsequent development of a remote mycotic pseudoaneurysm in the ipsilateral brachial artery following right transradial coronary angiography in a diabetic patient with previous right axillary node clearance. The potential for serious complication should be borne in mind when deciding on the site of vascular access in such patients.

Biochemical evidence of myocardial fibrosis in veteran endurance athletes

BACKGROUND

Studies on exercise-induced left ventricular hypertrophy (LVH) in veteran athletes suggest the presence of abnormal diastolic filling and incomplete regression of LVH on cessation of exercise.

HYPOTHESIS

Myocardial fibrosis occurs in exercise induced LVH in veteran athletes.

AIM

To document non-invasively the presence of fibrosis in veteran athletes

DESIGN

Prospective case-control study.

SETTING

City centre district general hospital.

PARTICIPANTS

45 normotensive elite veteran athletes and 45 normal sedentary subjects.

INTERVENTIONS

Echocardiographic assessment was made of LV mass, LV systolic and LV diastolic function. Plasma carboxyterminal propeptide of collagen type I (PICP), carboxyterminal telopeptide of collagen type I (CITP) and tissue inhibitor of matrix metalloproteinase type I (TIMP-1) were measured as markers of collagen synthesis, degradation and inhibition of degradation, respectively.

RESULTS

Veteran athletes had significant elevation in LV dimensions and calculated LV mass index (LVMI). Diastolic and systolic function was normal. Plasma PICP (259 vs 166 microg/l, p<0.001), CITP (5.4 vs 2.9 microg/l, p<0.001) and TIMP-1 (350 vs 253 ng/ml, p = 0.01) were elevated in the cohort of athletes. There was a further elevation of TIMP-1 in athletes with echocardiographic LVH, defined as an LVMI >130 g/m(2) (417 vs 266 ng/ml, p = 0.02).

CONCLUSION

There is biochemical evidence of disruption of the collagen equilibrium favouring fibrosis in veteran athletes with LVH. This may suggest that fibrosis occurs as part of the hypertrophic process in veteran athletes.

Hypertensive heart disease and fibrosis

PURPOSE OF REVIEW

The clinical importance of fibrosis in hypertensive heart disease is now well recognized. However, the precise mechanisms involved in the pathophysiology and therefore the potential cardioreparative strategies are still not fully understood. These areas continue to be the focus of extensive research. This review summarizes the work conducted in this field over the past 12 months.

RECENT FINDINGS

This article further confirms the involvement of the renin-angiotensin system in cardiac fibrosis and illustrates the supportive roles of mineralocorticoids, endothelin, and novel signaling pathways. It also summarizes the most recent data examining the genetic aspects of myocardial fibrosis and further clarifies potential cardioreparative strategies.

SUMMARY

Myocardial fibrosis in hypertensive heart disease remains an area of intensive research. Whereas recent work has expanded our knowledge of the underlying processes in the development of this fibrosis, additional scientific and clinical research is required to assist clinical risk assessment and to provide evidence that therapeutic intervention confers improved clinical outcome in hypertensive heart disease.

TIMP-1: a marker of left ventricular diastolic dysfunction and fibrosis in hypertension

This study was designed to document noninvasively the pathological mechanisms responsible for myocardial fibrosis and to assess the clinical utility of plasma markers of collagen synthesis and degradation as screening tools for the assessment of fibrosis in hypertension. We studied 100 never-treated hypertensive patients and 50 normal subjects. Echocardiographic assessment was made of left ventricular (LV) mass and diastolic filling using measurement of E:A ratio, E wave deceleration time (E dec), and isovolumic relaxation time (IVRT). The presence of diastolic dysfunction was taken as a surrogate marker for the presence of myocardial fibrosis. Plasma carboxy-terminal propeptide of collagen type I (PICP), carboxy-terminal telopeptide of collagen type I (CITP), and tissue inhibitor of matrix metalloproteinases type I (TIMP-1) were measured as markers of collagen synthesis, degradation, and inhibition of degradation, respectively. Plasma TIMP-1 was significantly elevated in the hypertensive cohort (358 ng/mL versus 253 ng/mL, P<0.001) as were CITP (5.2 microg/L versus 2.9 microg/L, P<0.001), and PICP (200 microg/L versus 166 microg/L, P<0.05). TIMP-1 was significantly elevated in patients with diastolic dysfunction (421 ng/mL versus 283 ng/mL P<0.01) and correlated with markers of diastolic filling, namely E:A ratio (r=0.26, P<0.05) and E Dec (r=0.41, P<0.01). A plasma TIMP-1 level of >500 ng/mL had a specificity of 97% and a positive predictive value of 96% in predicting diastolic dysfunction. In patients with untreated hypertension, there is evidence of increased collagen synthesis, degradation, and inhibition of degradation resulting in fibrosis. Our results demonstrate that plasma TIMP-1 correlates with markers of LV diastolic filling, is predictive of LV dysfunction, and is a potential noninvasive marker of fibrosis.

Optimising direct access ECHO referral in suspected heart failure

The objective was to prospectively validate a method of increasing the sensitivity, specificity and negative predictive value of a normal ECG in the exclusion of left ventricular systolic dysfunction by the addition of clinical history. We performed a prospective three year study of all referrals to our direct access ECHO service for assessment of LV function. The ECG was reported blind of the result of the ECHO, history of MI or not was noted, and result of the ECHO predicted. Over three years 416 patients were assessed for the presence or absence of left ventricular systolic dysfunction and consequent changes in clinical management. A total of 320(77%) of patients referred with suspected left ventricular dysfunction were found to have normal left ventricular function. Of the 250(60%) patients treated prior to referral for assessment, 183(73%) were treated inappropriately. The combination of a normal ECG and a negative history of myocardial infarction had a sensitivity of 98% and a negative predictive value of 99% in the assessment of LV function. This was an improvement over a normal ECG alone. Our study shows that diagnosis and treatment of heart failure in the community remains sub-optimal. The combination of a normal ECG and no previous history of myocardial infarction is shown to be a sensitive and accurate predictor of normal left ventricular function. If adopted by general practitioners this would be a valuable method of optimising the use of echocardiography in patients with suspected left ventricular dysfunction.