Estimation of B-type Natriuretic Peptide Values from N-Terminal proBNP Levels

Brain natriuretic peptide measurements using standard biochemical equipment: Comparisons with conventional immunoassays

Background

Brain natriuretic peptide (BNP) is an essential cardiac biomarker for diagnosing heart failure and for prognoses in patients with various cardiac diseases. However, measurement requires immunological assays that are not available in every hospital. Recently, a novel BNP kit (Nanopia BNP-A, Sekisui Inc.; BNPn) that uses general-purpose, automated, biochemical analyzers has become commercially available. We assessed how its accuracy and utility compare with those of conventional immunological tests.

Methods and results

We retrospectively collected 1491 conventional BNP measurements (BNPc), which had been clinically indicated for BNP testing and for which residual samples were still stored in the laboratory. We measured BNP using the novel kit and determined the correlation of BNP levels between the two methods. We also assessed the predictive value of both BNP measurements for major cardiac events (MACEs). The analytical performance of both measuring methods was similar. Log-transformed BNP measured by both methods showed strong correlation (r = 0.92); however, log-transformed BNPn was significantly higher than log-transformed BNPc (p<0.001). BNPc of 200 ng/L was used to stratify patients into two groups. According to the regression formula between the two methods, we determined a cut-off value of BNPn as 250 ng/L. During a median of 15 months of follow-up, 43 MACEs developed. Both BNPc and BNPn were associated with MACEs. Kaplan-Meier survival analysis indicated that both BNPc and BNPn cut-off values stratified the high-risk group for prognostication. The diagnostic and prognostic utilities were proven even if the lower cut-off values (BNPc = 100 ng/L, BNPn = 130 ng/L) were employed.

Conclusions

A new BNP measurement using biochemical equipment provides prognostic value similar to that of conventional BNP analysis; thus, it should prove useful in hospitals in which conventional immunological examinations are not available.

Optimal timing of echocardiography for heart failure inpatients in Japanese institutions: OPTIMAL Study

AIMS

Guidelines for the diagnosis and treatment of acute and chronic heart failure (HF) provided by the European Society of Cardiology state that echocardiography is recommended for the assessment of the myocardial structure and function of subjects with suspected HF including HF with reduced (HFrEF), mid-range (HFmrEF), and preserved ejection fraction (HFpEF) as class I of recommendation and level C of evidence. However, the impact of timing of echocardiography on survival for hospitalized HF patients or the prevalence of echocardiography during their stay has not yet been fully investigated. Therefore, we designed and conducted a prospective multicentre study, Optimal Timing of Echocardiography for Heart Failure Inpatients in Japanese Institutions (OPTIMAL) study, to investigate and evaluate the prevalence of echocardiography during the in-hospital stay of HF patients, and the impact of timing of echocardiography on their survival.

METHODS AND RESULTS

OPTIMAL was based on a nationwide, prospective, multicentre registry at 10 institutions in Japan endorsed by the Japanese Society of Echocardiography. A total of 601 patients hospitalized with HF were enrolled between August 2016 and July 2018 at the participating centres. Their mean age was 73.9 ± 13.0 years, left ventricular ejection fraction was 37.0% (26.0-50.0), and 256 patients (42.6%) were female. Admission echocardiography (admission echo) was categorized as either standard or point-of-care echocardiography performed within 3 days of admission, as was pre-discharge echocardiography (pre-discharge echo) within 3 days of discharge. The primary endpoint was defined as cardiovascular death over a median follow-up period of 18.9 months (9.3-26.5 months). Admission echo was performed for 476 patients (79.2%) and pre-discharge echo for 216 patients (35.9%). The primary endpoint of cardiovascular death occurred in 65 patients (10.8%). Kaplan-Meier curve findings indicated that survival of patients with pre-discharge echo was significantly better than that of patients without it (log-rank P < 0.001), and the same findings were obtained for patients with HFrEF, HFmrEF, and HFpEF. However, survival of patients with and without admission echo was similar (log-rank P = 0.33).

CONCLUSIONS

This OPTIMAL study prospectively showed the importance of pre-discharge echo for hospitalized HF patients. Careful attention is needed regarding the haemodynamic status of HF patients by administering pre-discharge echo to avoid HF re-hospitalization after discharge, and pre-discharge echo may provide additional information for deciding the appropriate discharge time. Our findings may thus offer a new insight into the management of hospitalized HF patients.

Cirrhotic Cardiomyopathy

PURPOSE OF REVIEW

Cirrhotic cardiomyopathy is a syndrome of depressed cardiac function in patients with cirrhosis. We aimed to review the historical background, pathophysiology and pathogenesis, diagnostic definitions, clinical relevance, and management of this syndrome.

RECENT FINDINGS

An inflammatory phenotype underlies the pathogenesis: gut bacterial translocation with endotoxemia stimulates cytokines and cardiodepressant factors, such as nitric oxide and endocannabinoids. Cardiomyocyte plasma membrane biochemical and biophysical changes also play a pathogenic role. These factors lead to impaired beta-adrenergic function. Proposed new echocardiographic criteria for the diagnosis of cirrhotic cardiomyopathy include systolic global longitudinal strain and indices of diastolic dysfunction. Cardiac dysfunction participates in the pathogenesis of hepatorenal syndrome and increased morbidity/mortality of cirrhotic patients to hemorrhage, infection, and surgery, including liver transplantation. There is no specific treatment, although β-adrenergic blockade and supportive management have been proposed, but it needs further study. Cirrhotic cardiomyopathy is a clinically relevant syndrome afflicting patients with established cirrhosis. Optimum management remains unclear, and further study is needed in this area.