Advances in coronary heart disease surgery in Latin America

High versus low blood pressure targets for cardiac surgery while on cardiopulmonary bypass

BACKGROUND

Cardiac surgery is performed worldwide. Most types of cardiac surgery are performed using cardiopulmonary bypass (CPB). Cardiac surgery performed with CPB is associated with morbidities. CPB needs an extracorporeal circulation that replaces the heart and lungs, and performs circulation, ventilation, and oxygenation of the blood. The lower limit of mean blood pressure to maintain blood flow to vital organs increases in people with chronic hypertension. Because people undergoing cardiac surgery commonly have chronic hypertension, we hypothesised that maintaining a relatively high blood pressure improves desirable outcomes among the people undergoing cardiac surgery with CPB.

OBJECTIVES

To evaluate the benefits and harms of higher versus lower blood pressure targets during cardiac surgery with CPB.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search of databases was November 2021 and trials registries in January 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing a higher blood pressure target (mean arterial pressure 65 mmHg or greater) with a lower blood pressure target (mean arterial pressure less than 65 mmHg) in adults undergoing cardiac surgery with CPB.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Primary outcomes were 1. acute kidney injury, 2. cognitive deterioration, and 3. all-cause mortality. Secondary outcomes were 4. quality of life, 5. acute ischaemic stroke, 6. haemorrhagic stroke, 7. length of hospital stay, 8. renal replacement therapy, 9. delirium, 10. perioperative transfusion of blood products, and 11. perioperative myocardial infarction. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included three RCTs with 737 people compared a higher blood pressure target with a lower blood pressure target during cardiac surgery with CPB. A high blood pressure target may result in little to no difference in acute kidney injury (risk ratio (RR) 1.30, 95% confidence interval (CI) 0.81 to 2.08; I² = 72%; 2 studies, 487 participants; low-certainty evidence), cognitive deterioration (RR 0.82, 95% CI 0.45 to 1.50; I² = 0%; 2 studies, 389 participants; low-certainty evidence), and all-cause mortality (RR 1.33, 95% CI 0.30 to 5.90; I² = 49%; 3 studies, 737 participants; low-certainty evidence). No study reported haemorrhagic stroke. Although a high blood pressure target may increase the length of hospital stay slightly, we found no differences between a higher and a lower blood pressure target for the other secondary outcomes. We also identified one ongoing RCT which is comparing a higher versus a lower blood pressure target among the people who undergo cardiac surgery with CPB.

AUTHORS' CONCLUSIONS

A high blood pressure target may result in little to no difference in patient outcomes including acute kidney injury and mortality. Given the wide CIs, further studies are needed to confirm the efficacy of a higher blood pressure target among those who undergo cardiac surgery with CPB.

The impact of relative hypotension on acute kidney injury progression after cardiac surgery: a multicenter retrospective cohort study

BACKGROUND

Cardiac surgery is performed worldwide, and acute kidney injury (AKI) following cardiac surgery is a risk factor for mortality. However, the optimal blood pressure target to prevent AKI after cardiac surgery remains unclear. We aimed to investigate whether relative hypotension and other hemodynamic parameters after cardiac surgery are associated with subsequent AKI progression.

METHODS

We retrospectively enrolled adult patients admitted to 14 intensive care units after elective cardiac surgery between January and December 2018. We defined mean perfusion pressure (MPP) as the difference between mean arterial pressure (MAP) and central venous pressure (CVP). The main exposure variables were time-weighted-average MPP-deficit (i.e., the percentage difference between preoperative and postoperative MPP) and time spent with MPP-deficit > 20% within the first 24 h. We defined other pressure-related hemodynamic parameters during the initial 24 h as exploratory exposure variables. The primary outcome was AKI progression, defined as one or more AKI stages using Kidney Disease: Improving Global Outcomes' creatinine and urine output criteria between 24 and 72 h. We used multivariable logistic regression analyses to assess the association between the exposure variables and AKI progression.

RESULTS

Among the 746 patients enrolled, the median time-weighted-average MPP-deficit was 20% [interquartile range (IQR): 10-27%], and the median duration with MPP-deficit > 20% was 12 h (IQR: 3-20 h). One-hundred-and-twenty patients (16.1%) experienced AKI progression. In the multivariable analyses, time-weighted-average MPP-deficit or time spent with MPP-deficit > 20% was not associated with AKI progression [odds ratio (OR): 1.01, 95% confidence interval (95% CI): 0.99-1.03]. Likewise, time spent with MPP-deficit > 20% was not associated with AKI progression (OR: 1.01, 95% CI 0.99-1.04). Among exploratory exposure variables, time-weighted-average CVP, time-weighted-average MPP, and time spent with MPP < 60 mmHg were associated with AKI progression (OR: 1.12, 95% CI 1.05-1.20; OR: 0.97, 95% CI 0.94-0.99; OR: 1.03, 95% CI 1.00-1.06, respectively).

CONCLUSIONS

Although higher CVP and lower MPP were associated with AKI progression, relative hypotension was not associated with AKI progression in patients after cardiac surgery. However, these findings were based on exploratory investigation, and further studies for validating them are required. Trial Registration UMIN-CTR, https://www.umin.ac.jp/ctr/index-j.htm , UMIN000037074.

Sex differences in health care-seeking behavior for acute coronary syndrome in a low income country, Peru

OBJECTIVE

: Recognizing reasons for prehospital delay after symptoms of acute coronary syndrome (ACS) is established in developed countries yet evidence from Latin America is limited. We aimed to assess ACS symptom recognition, health care-seeking behavior, and confidence in local health care facilities to take care of ACS by gender in a sample of Peruvians.

METHODS

: A community-based interview survey in a peri-urban area in Lima, Peru. The 24-item study instrument included vignettes and questions assessing identification of urgent and emergent ACS symptoms, anticipated help-seeking behaviors, and confidence in local health care facilities.

RESULTS

: In the study population (90 people; 45.6% men; mean age, 43.5 years), women were 4 times less likely to correctly attribute symptoms of chest pain to the heart (OR = 0.23; 95% CI: 0.063-0.87; P = 0.03). Women were much more likely to respond that a man would "Seek help" (OR = 4.54; 95% CI: 1.21-16.90; P = 0.024) and that "Yes," a woman would be less likely to seek help for chest pain symptoms (OR = 3.26; 95% CI: 1.13-9.41 P = 0.029) after adjusting for age, education level, age at migration, and history of chest pain. Women were less likely than men to think that their local Health Care Post would help them if they had a heart attack (2.1% vs. 14.6%; P = 0.04), and only 18.7% of women believed that their local emergency room would help them.

CONCLUSIONS

: Our findings suggest women are less likely to seek help for chest pain and women and men in a peri-urban area in Peru are not confident in their local health care facility to treat urgent or emergent ACS symptoms.

Lactosylceramide promotes cell migration and proliferation through activation of ERK1/2 in human aortic smooth muscle cells

Increased plasma levels of lactosylceramide (LacCer) have been associated with cardiovascular disease. However, it is largely unknown whether LacCer directly contributes to dysfunction of smooth muscle cells (SMCs), a key event in vascular lesion formation. In the present study, we determined the effects and potential mechanisms of LacCer on cell migration and proliferation in human aortic SMCs (AoSMCs). Cell migration and proliferation were determined by a modified Boyden chamber assay and nonradioactive colorimetric (MTS) assay, respectively. We found that LacCer significantly induced AoSMC migration and proliferation in a concentration- and time-dependent manner. In addition, LacCer significantly upregulated the expression of PDGFR-B, integrins (alpha(v) and beta(3)), and matrix metalloproteinases (matrix metalloproteinase-1 and -2) at both mRNA and protein levels, as determined by real-time PCR and Western blot analyses, respectively. Furthermore, LacCer increased superoxide anion production and the transient phosphorylation of ERK1/2 in AoSMCs, as determined by dihydroethidium staining and immunoassay, respectively. Accordingly, LacCer-induced cell migration and proliferation were effectively blocked by antioxidants (seleno-l-methionine and Mn tetrakis porphyrin) and by a specific ERK1/2 inhibitor. Thus, LacCer promotes cell migration and proliferation through oxidative stress and activation of ERK1/2 in AoSMCs. These findings demonstrate the functional role of LacCer in the vascular disease pathogenesis.