C-reactive protein and procalcitonin use in adults in low- and middle-income countries: a narrative review.

Objectives: C-reactive protein (CRP) and procalcitonin (PCT) are widely used biomarkers in high-income countries. However, evidence for their use in low- and middle-income countries (LMICs) is scant. Because many factors, including rates of endemic disease, comorbidities and genetics, may influence biomarkers' behaviour, we aimed to review available evidence generated in LMICs. Methods: We searched the PubMed database for relevant studies within the last 20 years that originated in regions of interest (Africa, Latin America, Middle East, South Asia or South East Asia), and full-text articles involving diagnosis, prognostication and evaluation of therapeutic response with CRP and/or PCT in adults (n = 88) were reviewed and categorized in 12 predefined focus areas. Results: Overall, results were highly heterogeneous, at times conflicting, and often lacking clinically useful cut-off values. However, most studies demonstrated higher levels of CRP/PCT in patients with bacterial versus other infections. HIV and TB patients had consistently higher levels of CRP/PCT versus controls. In addition, higher CRP/PCT levels at baseline and follow-up in HIV, TB, sepsis and respiratory tract infections were associated with poorer prognosis. Conclusions: Evidence generated from LMIC cohorts suggests that CRP and PCT may have potential to become effective clinical guiding tools particularly in respiratory tract infections, sepsis and HIV/TB. However, more studies are needed to define potential scenarios for use and cost-effectiveness. Consensus across stakeholders regarding target conditions, laboratory standards and cut-off values would support the quality and applicability of future evidence.

Impact of tricuspid valve regurgitation in patients treated with implantable left ventricular assist devices.

BACKGROUND: The progression of tricuspid valve regurgitation (TR) and the impact of preoperative TR on postoperative outcomes in patients having left ventricular assist device (LVAD) implantation has not been studied. METHODS: One hundred seventy-six consecutive implantable LVAD procedures were retrospectively reviewed. A total of 137 patients comprised the final study group with complete preimplant characteristics, before and after echocardiogram assessment of TR, and outcomes data. Patients were divided into two groups: insignificant TR (iTR) consisting of those with preimplant TR grades of none, trace, and mild; and significant TR (sTR) consisting of those with moderate and severe TR grades. RESULTS: Relative to patients with iTR, patients with sTR were younger (53.6±12.8 versus 58.4±10.0 years, p=0.02) and more commonly had nonischemic cardiomyopathies (69% versus 38%, p<0.001). The preimplant incidence of iTR and sTR was 51% and 49%. Immediately after the LVAD implant procedure, TR did not significantly change. At late follow-up (156±272 days), 32% had moderate or severe TR. Also, 41% of the original sTR group persisted with moderate or severe TR. Relative to patients with iTR, patients with sTR required longer postimplant intravenous inotropic support (8.5 versus 5.0 days, p=0.02), more commonly required a temporary right ventricular assist device, and had a longer postimplant length of hospital stay (27.0 versus 20.0 days, p=0.03). There was also a trend toward decreased survival for sTR versus iTR (log rank=0.05). CONCLUSIONS: Tricuspid regurgitation is not reduced immediately after LVAD implantation. Significant TR is associated with longer postimplant inotropic support and length of hospital stay.

Impact of left ventricular assist device bridging on posttransplant outcomes.

BACKGROUND: Bridge to heart transplantation with a left ventricular assist device (LVAD) can be a promising therapy for patients who are not effectively stabilized with conservative measures. However, referral for LVAD therapy may be limited secondary to reports of poor outcomes when mechanical circulatory support is required before transplantation. METHODS: A retrospective review was undertaken to evaluate outcomes in United Network of Organ Sharing (UNOS) status 1 heart transplant recipients who were bridged to transplant with an implantable LVAD or with intravenous inotropes only from 1994 to 2007. Preoperative characteristics, posttransplant survival, and postoperative complications were compared between 86 patients with an implantable LVAD and 173 patients bridged with intravenous inotropes only. RESULTS: The patients had similar baseline characteristics and pretransplant hemodynamics. Hemodynamics in the LVAD group, as measured by cardiac index, pulmonary vascular resistance, central venous pressure, and pulmonary capillary wedge pressure, significantly improved during mechanical support. Short-term and long-term posttransplant survival and the incidence of posttransplant infectious complications and rejection episodes during the first year was similar. The incidence of posttransplant renal dysfunction was higher in patients bridged with inotropes. CONCLUSIONS: Patients bridged to transplant with a LVAD represent a subset of UNOS status 1 patients who deteriorated on intravenous inotropic therapy. Bridging to heart transplantation with an implantable LVAD provides comparable outcomes to similar status 1 patients who were stabilized on inotropic infusions only. In contrast with International Society of Heart and Lung Transplantation data, no increase in posttransplant morbidity or mortality occurred in LVAD-bridged patients.