Improving quality and reducing inequality in heart failure

The popular annual autumn meeting of the British Society for Heart Failure (BSH) boasted a line-up of internationally recognised authorities in heart failure. Held in London on 28^th-29^th November 2019, the meeting's focus was on improving quality and reducing inequality. Drs Sanjay S Bhandari and Daniel CS Chan report its highlights.

Recurrent valve obstruction in a patient with a pure carbon bileaflet metallic mitral valve: a case report

Background

Despite overcoming the morbidity from severe native valve disease, prosthetic metallic valve replacement is not without its inherent morbidity, in particular from prosthetic valve thrombosis (PVT). The contemporary pure carbon bileaflet metallic valve confers reduced thrombogenicity.

Case Summary

We describe the case of a 45-year-old woman with a pure carbon bileaflet metallic mitral valve replacement (27/29 mm On-X) 6 months previously for severe rheumatic mitral stenosis, who presented with a rapid onset of dyspnoea, paroxysmal nocturnal dyspnoea, and haemoptysis. This was preceded by an interruption in therapeutic anticoagulation. On admission the patient was in cardiogenic shock. Transthoracic and transoesophageal (TOE) echocardiograms revealed increased transmitral gradients with disc hypomobility, suggestive of PVT, unexpected given the favourable safety profile of the On-X valve. Fluoroscopy confirmed the findings. The patient was thrombolysed successfully with alteplase, with restoration of normal transmitral gradients. A target international normalized ratio of 3.5–4.5 was chosen, in addition to aspirin 75 mg, to minimize thrombotic sequalae. Repeat TOE 6 weeks later revealed disc hypomobilty with a large adherent clot. Due to the high risks from thrombolysis, emergency redo-mitral bioprosthetic valve surgery was performed, to negate the need for long-term anticoagulation.

Discussion

Subtherapeutic anticoagulation and the rapid development of dyspnoea, should prompt the clinician to suspect PVT. Thorough clinical examination and immediate bedside echocardiography are critical for assessing prosthetic valve patients in cardiogenic shock. The treatment of PVT is complex, with considerable risks to the patient, irrespective of the strategy (thrombolysis/emergency valve replacement), necessitating the expertise of cardiologists and cardiac surgeons.

Mesalazine induced myopericarditis in a patient with ulcerative colitis

A 25-year-old male with a background of ulcerative colitis presented with a two-week history of central chest pain. His ECG on presentation showed global T wave inversion with a peak troponin I of 165 ng/ml. Clinical diagnosis of myopericarditis/myocarditis was made. Echocardiography and cardiac MR confirmed the diagnosis. On detailed assessment of his medication history, mesalazine was suspected as an aetiological factor, with discontinuation resulting in an improvement in symptoms, inflammatory markers and cardiac enzymes. This is a unique case of mesalazine induced myopericarditis on a background of inflammatory bowel disease.

An uncommon manifestation of shock: Takotsubo syndrome

76-year-old female presented following an episode of collapse. She was hypotensive with the paramedics and remained refractory despite fluid resuscitation. Her initial baseline tests revealed an elevated troponin; she subsequently underwent a coronary angiogram that showed mild coronary artery disease. Left ventriculogram was performed, which showed abnormal mid-wall ballooning and severely impaired systolic function, characteristic of Takotsubo syndrome. Echocardiogram confirmed the presence of diagnosis and presence of left ventricular outflow tract obstruction with high gradient. She was initiated on medical heart failure therapy and improved. Follow-up investigations after 2 months showed complete resolution of systolic dysfunction and symptoms.

Critical aortic stenosis presenting as STEMI

A 73-year-old male was brought into hospital with chest pain and inferior ST elevation on ECG. The patient immediately proceeded to the catheter lab for primary percutaneous coronary intervention. Angiography did not identify any culprit lesions to account for the patient’s electrocardiographic changes and ongoing symptoms of chest pain. Bedside echocardiography revealed critical aortic stenosis. Intra-aortic balloon pump (IABP) was inserted, resulting in resolution of chest pain and ST-segment changes. The patient underwent successful aortic valve (AV) replacement without the need for coronary intervention. This is a rare presentation of critical aortic stenosis (AS) presenting as ST-segment elevation myocardial infarction (STEMI).

Trimethylamine N-oxide and prognosis in acute heart failure

OBJECTIVE

Acute heart failure (AHF) is associated with high mortality and morbidity. Trimethylamine N-oxide (TMAO), a gut-derived metabolite, has reported association with mortality risk in chronic HF but this association in AHF is still unknown. The present study investigated TMAO in patients admitted to hospital with AHF, and association of circulating levels with prognosis.

METHODS

In total, 972 plasma samples were analysed for TMAO concentration by liquid chromatography-mass spectrometry. Associations with in-hospital mortality (72 events), all-cause mortality (death, 268 events) and a composite of death or rehospitalisation due to HF (death/HF, 384 events) at 1 year were examined.

RESULTS

TMAO improved risk stratification for in-hospital mortality in combination with current clinical scorings (OR≥1.13, p≤0.014). TMAO tertile analyses reported a graded risk in adverse outcome within 1 year (OR≥1.61, p≤0.004) and improved outcome prediction when stratified as none, one or both biomarker(s) elevated in combination with N-terminal pro B-type natriuretic peptide (NT-proBNP) (OR≥2.15, p≤0.007). TMAO was independently predictive for death and death/HF when corrected for cardiac risk factors (HR≥1.16, p≤0.037); however, this ability was weakened when indices of renal function were included, possibly due to multicollinearity.

CONCLUSIONS

TMAO contributed additional information on patient stratification for in-hospital mortality of AHF admissions using available clinical scores that include renal indices. Furthermore, elevated levels were associated with poor prognosis at 1 year and combination of TMAO and NT-proBNP provided additional prognostic information. TMAO was a univariate predictor of death and death/HF, and remained an independent predictor until adjusted for renal confounders.

Growth hormone for risk stratification and effects of therapy in acute myocardial infarction

CONTEXT

Excess growth hormone (GH) is associated with early mortality.

OBJECTIVES

We assessed the association of GH with prognosis after acute myocardial infarction (AMI), and the effects of secondary prevention therapies.

METHODS

GH was measured using a high-sensitivity assay in 953 AMI patients (687 males, mean age 66.1 ± 12.8 years).

RESULTS

During 2 years follow-up, there were 281 major adverse cardiac events (MACE). Patients with MACE had higher GH levels (median [range], 0.91 [0.04-26.28] μg/L) compared to event-free survivors (0.59 [0.02-21.6], p < 0.0005). In multivariate Cox survival analysis, GH was a significant predictor of MACE (hazard ratios 1.43, p = 0.026 and 1.49, p = 0.01, respectively) with significant interactions with beta blocker therapy (p = 0.047) and angiotensin converting enzyme inhibitor or angiotensin receptor blocker (ACE/ARB) therapy (p = 0.016).

CONCLUSIONS

GH levels post-AMI are prognostic for MACE and may indicate those patients who benefit from beta blocker and ACE/ARB therapy.

Plasma C-terminal proEndothelin-1 (CTproET-1) is affected by age, renal function, left atrial size and diastolic blood pressure in healthy subjects

Endothelin-1 (ET-1) is a short chained peptide primarily of endothelial origin. Concentrations of this peptide are increased in subjects with hypertension, primary pulmonary hypertension and myocardial infarction, however its short half-life makes quantification difficult. The C-terminal of proET-1 (CTproET-1) is stoichiometrically secreted with its bioactive peptide and would be a valid method of measuring the active peptide as it has a stable half-life and is less resistant to proteolytic cleavage. The objective of this study was to understand the factors (clinical, echocardiographic and biochemical) that specifically influence plasma CTproET-1 in healthy subjects. 518 healthy volunteers were recruited from a screening study. Plasma CTproET-1 concentrations were quantified using a novel immunoluminometric sandwich assay. In multivariate analyses, age (P<0.001), diastolic BP (P=0.007), LA size (P=0.001) and eGFR (P<0.001) were independently predictive of plasma CTproET-1 levels in the healthy subjects. Therefore the interpretation of plasma CTproET-1 levels in such individuals should take into account these variables to avoid potential confounding.

The diagnostic performance of mid-regional portion of pro-atrial natriuretic peptide for the detection of left ventricular hypertrophy in Caucasian hypertensive patients

Left ventricular hypertrophy (LVH) is predictive of cardiovascular disease. The vasodilator, natriuretic and diuretic actions of atrial natriuretic peptide (ANP) support a role in the pathophysiology of hypertension. Measuring the redundant precursor fragment mid-regional portion of pro-atrial natriuretic peptide (MRproANP) overcomes the technical difficulties of quantifying the bioactive ANP. This study sought to investigate the diagnostic and prognostic utility of MRproANP in a hypertensive Caucasian patient population. A total of 194 hypertensive patients (39 patients with LVH, 69±7.82 years of age, 74% female vs 155 patients without LVH, 68±6.51 years of age, 71% female) were derived from a screening study. Plasma MRproANP concentrations were quantified using immunoluminometric assays. Hypertensive patients with LVH had higher MRproANP concentrations than those without LVH (103.04 (50.58) vs 84.11 pmol l(-1) (44.82); P=0.014). Independent predictors of left ventricular mass index were LogMRproANP (P=0.022), male gender (P<0.001), body mass index (P=0.001) and history of angina or myocardial infarction (P=0.009). The receiver operating curve for MRproANP for the detection of LVH was limited, yielding an area under the curve of only 0.628 (confidence interval 0.523-0.733; P=0.014). Therefore, the role of MRproANP may not lie in the diagnosis of LVH but in monitoring the response to therapy. A nonsignificant trend towards greater mortality in patients with above-median MRproANP levels compared with below-median levels (P=0.167) was observed. Larger studies are required to assess its prognostic utility further.

The midregional portion of proadrenomedullin is an independent predictor of left ventricular mass index in hypertension

Left ventricular hypertrophy (LVH) is a risk factor for cardiovascular disease. Elevated natriuretic peptides in LVH have spurred interest that biomarkers may play a role in screening programs. Adrenomedullin (ADM) is a 52-amino acid peptide mediating vasorelaxation, natriuresis, and diuresis. The midregional portion of proADM (MRproADM) is secreted stoichiometrically with ADM; hence, it can be used as a surrogate marker of ADM. We compared the diagnostic performance of MRproADM for the detection of LVH with N-terminal pro-B-type natriuretic peptide (NTproBNP). Two hundred fifty-three hypertensive patients were derived from a local screening study. The MRproADM and NTproBNP levels were assayed using immunoluminometric assays. The MRproADM levels were significantly elevated in patients with LVH than those without (mean [SD]: 0.73 [0.25] vs 0.59 [0.18] nmol/L, P < .001). In multivariate analyses, male sex (P < .001) and log MRproADM (P = .003) retained significance for detecting LVH. Receiver operating characteristic curve for MRproADM yielded an area under the curve of 0.71; confidence interval, 0.62-0.81; P < .001, superior to NTproBNP. An optimal cutoff value for MRproADM as an indicator of LVH was 0.50 nmol/L, with a sensitivity, specificity, and negative predictive value of 90.5%, 36.5%, and 95.1%, respectively. The high negative predictive value of the MRproADM assay allows it to be used as a rule-out test for LVH when stratifying patients into high or low risk. Patients who test positive would necessitate echocardiography, enabling better resource allocation.

Urotensin II is raised in acute myocardial infarction and low levels predict risk of adverse clinical outcome in humans

BACKGROUND

UII is elevated in patients with heart failure; however its role in acute myocardial infarction (AMI) is unknown. We sought to compare levels of UII in patients with AMI to controls. We also compared UII to N terminal pro B type natriuretic peptide (NT-BNP) to evaluate whether levels of UII can be used to predict the risk of adverse clinical outcome (ACO).

METHODS AND RESULTS

129 patients were studied with serial blood measurements and echocardiogram during their index admission. Plasma concentration of median UII was significantly elevated in AMI compared to controls (median 1.40 vs. 0.42 fmol/ml p<0.012). Over the median follow up of 102 days (range 0-189) there were 14 deaths and 14 readmissions with AMI or heart failure. Using a Cox proportional hazards model the only independent predictors of ACO were UII (OR 0.29, p=0.046) and NT-BNP (OR 4.78, p=0.012) between 73 and 96 h. The Kaplan-Meier survival curve revealed a significantly better clinical outcome in patients with UII above the median compared with UII below the median.

CONCLUSIONS

UII levels are raised in AMI and is an independent predictor of ACO. Patients with a poor outcome mount a lower UII response suggesting a possible cardioprotective role for this peptide.