Plasma renin activity has a complex prognostic role in patients with acute coronary syndromes.

BACKGROUND: Plasma renin activity (PRA) has been related to all-cause mortality and cardiovascular events in patients with cardiovascular disease. However, data from patients with acute coronary syndromes (ACS) are sparse. METHODS: Determination of PRA was made in 550 patients with ACS, including a subgroup of 287 patients not on treatment with angiotensin converting enzyme inhibitors, angiotensin receptor blockers or diuretics, and without heart failure. We evaluated the relations between PRA and all-cause mortality after three years and long-term, and to cardiovascular events after median 8.7 years. Adjustments were made for variables that influenced the hazard ratio (HR) > 5% for the relation between PRA and outcome. RESULTS: Baseline PRA was associated with all-cause mortality during three-years (unadjusted HR 1.74 per 1 SD increase in logarithmically transformed PRA; 95% confidence interval (CI) 1.39-2.16, p < 0.0001) and long-term (HR 1.12, CI 1.00-1.25, p = 0.046). After adjustments, only the three-year association remained significant. In unadjusted analyses, PRA was associated with cardiovascular death, but not with nonfatal cardiovascular events. In the subgroup there was an inverse relation between PRA and long-term all-cause mortality. CONCLUSION: Higher PRA was a significant independent predictor of all-cause mortality after three years, but not at long-term follow-up and not significantly associated with cardiovascular incidence. The renin-angiotensin-system pathophysiology is of great interest, not least due to its association with the COVID-19 pandemic. Our findings indicate a need for further research on the prognostic/predictive aspects of the renin-angiotensin-system in ACS.

Intestinal dysbiosis is common in systemic sclerosis and associated with gastrointestinal and extraintestinal features of disease.

BACKGROUND: Recent evidence suggests a link between autoimmunity and the intestinal microbial composition in several rheumatic diseases including systemic sclerosis (SSc). The objective of this study was to investigate the prevalence of intestinal dysbiosis in SSc and to characterise patients suffering from this potentially immunomodulatory deviation. METHODS: This study consisted of 98 consecutive patients subject to in-hospital care. Stool samples were analysed for intestinal microbiota composition using a validated genome-based microbiota test (GA-map™ Dysbiosis Test, Genetic Analysis, Oslo, Norway). Gut microbiota dysbiosis was found present as per this standardised test. Patients were examined regarding gastrointestinal and extraintestinal manifestations of SSc by clinical, laboratory, and radiological measures including esophageal cineradiography, the Malnutrition Universal Screening Tool (MUST), levels of plasma transthyretin (a marker of malnutrition) and faecal (F-) calprotectin (a marker of intestinal inflammation). RESULTS: A majority (75.5%) of the patients exhibited dysbiosis. Dysbiosis was more severe (rs = 0.31, p = 0.001) and more common (p = 0.013) in patients with esophageal dysmotility. Dysbiosis was also more pronounced in patients with abnormal plasma levels of transthyretin (p = 0.045) or micronutrient deficiency (p = 0.009). In 19 patients at risk for malnutrition according to the MUST, 18 exhibited dysbiosis. Conversely, of the 24 patients with a negative dysbiosis test, only one was at risk for malnutrition. The mean ± SEM levels of F-calprotectin were 112 ± 14 and 45 ± 8 µg/g in patients with a positive and negative dysbiosis test, respectively. Dysbiosis was more severe in patients with skin telangiectasias (p = 0.020), pitting scars (p = 0.023), pulmonary fibrosis (p = 0.009), and elevated serum markers of inflammation (p < 0.001). However, dysbiosis did not correlate with age, disease duration, disease subtype, or extent of skin fibrosis. CONCLUSIONS: In this cross-sectional study, intestinal dysbiosis was common in patients with SSc and was associated with gastrointestinal dysfunction, malnutrition and with some inflammatory, fibrotic and vascular extraintestinal features of SSc. Further studies are needed to elucidate the potential causal relationship of intestinal microbe-host interaction in this autoimmune disease.

Effect of surgery on cardiac structure and function in mild primary hyperparathyroidism.

CONTEXT: The cardiovascular (CV) risk profile is worsened in primary hyperparathyroidism (PHPT), and CV mortality is related to serum calcium levels. It is unknown whether CV mortality is increased in the most common form of PHPT and whether the increased CV risk is reversible after surgery. OBJECTIVE: To investigate reversibility of echocardiographic variables in patients with mild PHPT who were randomized to observation without surgery or operation, and followed for 2 years. DESIGN/SETTING/PATIENTS: Forty-nine patients (mean age 63 ± 7 years, 8 men) who had performed the 2-year visit in a randomized study on mild PHPT (serum calcium at baseline 2·65 ± 0·09 mm) (observation) vs 2·67 ± 0·06 mm (surgery) and where echocardiography had been performed, participated in the study. RESULTS: Calcium and parathyroid hormone (PTH) levels were normalized following surgery and were stable in the observation group. PTH levels at baseline were highly correlated with ventricular mass. Detailed echocardiography revealed a minor and borderline significant treatment effect of surgery on left ventricular mass index (LVMI) compared to observation (P = 0·066) and a significant 11% reduction in diastolic dimension of the interventricular septum (IVSd-mean) in the surgery group (P<0·01), with no alterations in the observation group. CONCLUSIONS: Based on detailed echocardiographic measures over a 2-year observation period, we found only minor differences between the two groups. However, the potential treatment effect on LVMI and the within-group differences in IVSd-mean suggest that longer follow-up may yield larger and clinically important differences.

Long-term prognostic value of mitral regurgitation in acute coronary syndromes.

OBJECTIVES: To determine the additional prognostic value of mitral regurgitation (MR) over B-type natriuretic peptide (BNP), left ventricular ejection fraction (LVEF) and clinical characteristics in patients with acute coronary syndromes (ACS). DESIGN: Long-term follow-up in a prospective ACS cohort with Doppler-assessed MR, echocardiographically-determined LVEF and plasma BNP levels by ELISA. SETTING: Single-centre university hospital. PATIENTS: 725 patients with ACS. MAIN OUTCOME MEASURES: Death and readmission for congestive heart failure. RESULTS: During a median follow-up of 98 months, 235 patients (32%) died. Significant MR (grade >1 of 4) was found in 90 patients (12%). In a multivariate model including MR grade >1, LVEF <0.40 and BNP >373 pg/ml (75th percentile), MR was significantly associated with long-term mortality (HR 2.28, 95% CI 1.67 to 3.12; p<0.0001). When also adjusting for conventional risk factors, MR remained significantly associated with mortality (HR 1.53, 95% CI 1.06 to 2.19; p=0.02), as well as with congestive heart failure (HR 2.08, 95% CI 1.29 to 3.35; p=0.003). CONCLUSIONS: MR is common in patients with ACS, provides independent risk information and should be taken into account in the evaluation of the long-term prognosis.

Interleukin-18 as a predictor of future events in patients with acute coronary syndromes.

OBJECTIVE: The aim of this study was to assess the short- and long-term prognostic significance of interleukin-18 (IL-18) levels in patients with acute coronary syndromes (ACS). METHODS AND RESULTS: In patients hospitalized with ACS (median age, 66 years; 30% females), we evaluated associations of serum IL-18 levels from day 1 (n=1261) with the short- (<3 months) and long-term (median, 7.6 years) risk of death, development of congestive heart failure (CHF), and myocardial infarction (MI). IL-18 was not significantly associated with short-term mortality. In the long term, IL-18 levels were significantly related to all-cause mortality, even after adjustment for clinical confounders (hazard ratio [HR], 1.19; 95% confidence interval, 1.07 to 1.33; P=0.002). Long-term, cardiovascular mortality was univariately related to IL-18, and the adjusted relation between noncardiovascular mortality and IL-18 was highly significant (HR, 1.36; 95% confidence interval, 1.11 to 1.67; P=0.003). IL-18 independently predicted CHF, MI, and cardiovascular death/CHF/MI in both the short and long term. Measurements from day 1 of ACS and 3 months after ACS had a similar power to predict late outcome. CONCLUSIONS: The addition of the measurement of IL-18 to clinical variables improved the prediction of risk of all-cause and noncardiovascular mortality. The association between IL-18 and noncardiovascular mortality is intriguing and warrants further study.

Multivariate data analysis of factors affecting the in vitro dissolution rate and the apparent solubility for a model basic drug substance in aqueous media.

PURPOSE: To evaluate the usefulness of a miniaturized rotating disk equipment for the determination of factors influencing the in vitro dissolution rate, G, of a model basic drug substance (terfenadine) in different aqueous media, using experimental design and multivariate data analysis. The apparent solubility, S, was included in the chemometric study. METHODS: The dissolution rate was determined with a miniaturized rotating disk apparatus and the solubility by shake-flask methodology. Media were based on acetate, phosphate or maleate buffers-the latter used in fasted state simulated intestinal fluid (FaSSIF-V2). The chemometric analyses included fractional factorial design, principal component analysis (PCA) and orthogonal partial least squares (OPLS). Quantifications were made with a RP-HPLC-DAD system. RESULTS: The most influential factor for both G and S of terfenadine in the different media was pH. Apart from the ionic strength and sodium chloride concentration in the acetate medium, the effects of the other variables were insignificant, implying no wetting effect of the surfactants. CONCLUSIONS: The miniaturized rotating disk equipment was suitable to use, in conjunction with the chemometric analyses, in the evaluation of the factors affecting the in vitro dissolution rate. The apparent solubility was found to be influenced by the same factors as G.

Circulating osteoprotegerin levels and long-term prognosis in patients with acute coronary syndromes.

OBJECTIVES: This study was designed to assess the association between osteoprotegerin (OPG) levels on admission and long-term prognosis in patients with acute coronary syndromes (ACS). BACKGROUND: Osteoprotegerin, a member of the tumor necrosis factor receptor superfamily, has pleiotropic effects on bone metabolism, endocrine function, and the immune system. METHODS: Serum samples for OPG analysis were obtained within 24 h of admission in 897 ACS patients (median age 66 years, 71% men) and related to the incidence of death, heart failure (HF) hospitalizations, myocardial infarction (MI), and stroke. RESULTS: A total of 261 patients died during a median follow-up of 89 months. The baseline OPG concentration was strongly associated with increased long-term mortality (hazard ratio [HR] for HR per 1 SD increase in logarithmically transformed OPG level 1.7 [range 1.5 to 1.9] p < 0.0001) and HF hospitalizations (HR 2.0 [range 1.6 to 2.5]; p < 0.0001) but weaker with recurrent MI (HR 1.3 [range 1.0 to 1.5]; p = 0.02) and not with stroke (HR 1.2 [range 0.9 to 1.6]; p = 0.35). After adjustment for conventional risk markers, including troponin I, C-reactive protein (CRP), B-type natriuretic peptide (BNP), and ejection fraction, the association remained significant for mortality (HR 1.4 [range 1.2 to 1.7]; p < 0.0001) and HF hospitalization (HR 1.6 [range 1.2 to 2.1]; p = 0.0002), but not recurrent MI. By comparison of the area under the receiver-operating characteristics curves, OPG performed similarly to BNP and ejection fraction and significantly better than CRP and troponin I as a predictor of death. CONCLUSIONS: Serum OPG is strongly predictive of long-term mortality and HF development in patients with ACS, independent of conventional risk markers.

Design and characterization of a new miniaturized rotating disk equipment for in vitro dissolution rate studies.

A miniaturized apparatus for the determination of the apparent in vitro dissolution rate has been designed, constructed and characterized. The miniaturized apparatus was based on a low volume dissolution cell and a disk in a rotating magnetic bar. The disk tablet is pressed directly into the bar with a press designed and constructed for this purpose. It requires approximately 5 mg of substance. The disk was positioned eccentrically on the bar with an external flow of medium to increase the rate of solvent flow over the disk surface. Six different drug substances were used. The dissolution media were sodium phosphate buffer, pH 7.0, and ammonium acetate buffer, pH 6.8. All quantifications were made by integrating the dissolution cell with high-performance liquid chromatography (HPLC) using diode-array detection (DAD). The obtained results were compared with data from a conventional rotating disk equipment, where the disk was centrically mounted. The dissolution rates at 100 rpm seemed to be on an average of 2-3 times higher for the miniaturized apparatus (RSD 0.2-56%). The preliminary studies of this prototype indicate that the miniaturized rotating disk is a promising design for the qualitative estimation of dissolution rates of substances, for example during screening in early drug discovery.

Can the left ventricular early diastolic tissue-to-blood time interval be used to identify a normal pulmonary capillary wedge pressure?

The pulsed Doppler early diastolic left ventricular (LV) tissue (e)-blood (E) onset temporal relationship (e-E) is suggested to predict pulmonary capillary wedge pressure (PCWP), through the formulas: tau = 32 + 0.7(e-E) and PCWP = LV end-systolic pressure x e(-IVRT/tau). Small changes/errors in E could influence the quotient IVRT/tau by oppositely affecting IVRT and e-E. At rest in 50 healthy individuals we noted: e-E: 2 +/- 14 ms; IVRT: 89 +/- 17 ms; calculated tau: 33 +/- 10 ms; and PCWP: 9 +/- 9 mmHg (> 12 mmHg in 28%). Non-pharmacological preload alterations in 14 individuals rendered an intraindividual 'PCWP'-fluctuation of up to 40 mmHg. This application may therefore not be clinically robust.

Timing of regional left ventricular lengthening by pulsed tissue Doppler.

Pulsed tissue Doppler can measure myocardial velocities with high temporal resolution. Our aim was to determine the onset timing of the regional left ventricular longitudinal early lengthening (e) in relation to the mitral inflow (E) in acute coronary syndromes. We applied pulsed tissue Doppler to the septal, lateral, inferior, and anterior left ventricular basal walls of 160 patients with acute coronary syndromes and 60 control subjects. Maximum systolic and early diastolic velocities were lower for patient than for control walls (6.1 +/- 1.7 vs 7.9 +/- 1.4 cm/s, P <.0001, and 6.9 +/- 2.3 vs 10.0 +/- 2.3 cm/s, P <.0001, respectively) and e started later than E (12 +/- 30 vs 2 +/- 19 milliseconds later, P <.0001). All 3 variables related to the degree of visual left ventricular wall pathology. The intraindividual time range for all 4 e starts was wider for patients (43 +/- 27 vs 30 +/- 18 milliseconds, P <.0001). Our results show that pulsed tissue Doppler can identify a delayed and asynchronous initial wall lengthening in acute coronary syndromes.

N-terminal pro-B-type natriuretic peptide and long-term mortality in acute coronary syndromes.

BACKGROUND: B-type natriuretic peptide (BNP) is a predictor of short- and medium-term prognosis across the spectrum of acute coronary syndromes (ACS). The N-terminal fragment of the BNP prohormone, N-BNP, may be an even stronger prognostic marker. We assessed the relation between subacute plasma N-BNP levels and long-term, all-cause mortality in a large, contemporary cohort of patients with ACS. METHODS AND RESULTS: Blood samples for N-BNP determination were obtained in the subacute phase in 204 patients with ST-elevation myocardial infarction (MI): 220 with non-ST segment elevation MI and 185 with unstable angina in the subacute phase. After a median follow-up of 51 months, 86 patients (14%) had died. Median N-BNP levels were significantly lower in long-term survivors than in patients dying (442 versus 1306 pmol/L; P<0.0001). The unadjusted risk ratio of patients with supramedian N-BNP levels was 3.9 (95% confidence interval, 2.4 to 6.5). In a multivariate Cox regression model, N-BNP (risk ratio 2.1 [95% confidence interval, 1.1 to 3.9]) added prognostic information above and beyond Killip class, patient age, and left ventricular ejection fraction. Adjustment for peak troponin T levels did not markedly alter the relation between N-BNP and mortality. In patients with no evidence of clinical heart failure, N-BNP remained a significant predictor of mortality after adjustment for age and ejection fraction (risk ratio, 2.4 [95% confidence interval, 1.1 to 5.4]). CONCLUSIONS: N-BNP is a powerful indicator of long-term mortality in patients with ACS and provides prognostic information above and beyond conventional risk markers.