Extracorporeal membrane oxygenation without therapeutic anticoagulation in adults: A systematic review of the current literature

Extracorporeal membrane oxygenation is essential for the treatment of refractory cardiopulmonary failure. Its use may be complicated by worse haemorrhagic complications exacerbated by extracorporeal membrane oxygenation–related therapeutic anticoagulation. Progressive technological advancements have made extracorporeal membrane oxygenation components less thrombogenic, potentially allowing its application with temporary avoidance of systemic anticoagulants. A systematic review of all the available experiences, reporting the use of extracorporeal membrane oxygenation without systemic anticoagulation in the published literature was performed. Only patient series were included, irrespective of the clinical indication. The survival, extracorporeal membrane oxygenation system–related dysfunction and complications rates, as well as in-hospital outcome, were analysed. Six studies were selected for the analysis. Veno-arterial extracorporeal membrane oxygenation was used in 84% of patients, while veno-venous extracorporeal membrane oxygenation was applied in the remaining cases. Anticoagulation was avoided because of the high risk of bleeding after cardiac surgery (64%), active major bleeding (23%) or presence of severe traumatic injury (9%). Duration of support ranged from 0.3 to 1128 h. Heparin was antagonized by protamine in all the post-cardiotomy cases. Successfully extracorporeal membrane oxygenation weaning was achieved in 74% of the treated cases, with a hospital discharge of 58% of patients. Rates of extracorporeal membrane oxygenation malfunctioning due to clot formation and blood transfusion requirement varied remarkably in the published series. Extracorporeal membrane oxygenation without systemic anticoagulation appears feasible in selected circumstances. Further investigations are warranted to elucidate actual aspects regarding extracorporeal membrane oxygenation system performance, related adverse events and benefits associated with this management.

Transcatheter Aortic Valve Replacement with Self-Expandable ACURATE neo as Compared to Balloon-Expandable SAPIEN 3 in Patients with Severe Aortic Stenosis: Meta-Analysis of Randomized and Propensity-Matched Studies

Frequent occurrence of paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) was the main concern with earlier-generation devices. Current meta-analysis compared outcomes of TAVR with next-generation devices: ACURATE neo and SAPIEN 3. In random-effects meta-analysis, the pooled incidence rates of procedural, clinical and functional outcomes according to VARC-2 definitions were assessed. One randomized controlled trial and five observational studies including 2818 patients (ACURATE neo n = 1256 vs. SAPIEN 3 n = 1562) met inclusion criteria. ACURATE neo was associated with a 3.7-fold increase of moderate-to-severe PVL (RR (risk ratio): 3.70 (2.04-6.70); P < 0.0001), which was indirectly related to higher observed 30-day mortality with ACURATE valve (RR: 1.77 (1.03-3.04); P = 0.04). Major vascular complications, acute kidney injury, periprocedural myocardial infarction, stroke and serious bleeding events were similar between devices. ACURATE neo demonstrated lower transvalvular pressure gradients both at discharge (P < 0.00001) and at 30 days (P < 0.00001), along with lower risk of patient-prosthesis mismatch (RR: 0.29 (0.10-0.87); P = 0.03) and pacemaker implantation (RR: 0.64 (0.50-0.81); P = 0.0002), but no differences were observed regarding composite endpoints early safety and device success. In conclusion, ACURATE neo, as compared with SAPIEN 3, was associated with higher rates of moderate-to-severe PVL, which were indirectly linked with increased observed 30-day all-cause mortality.

The impact of Centre's heart transplant status and volume on in-hospital outcomes following extracorporeal membrane oxygenation for refractory post-cardiotomy cardiogenic shock: a meta-analysis

BACKGROUND

Postcardiotomy cardiogenic shock (PCS) that is refractory to inotropic support remains a major concern in cardiac surgery and is almost universally fatal unless treated with mechanical support. While reported mortality rates on ECMO vary from center to center, aim of the current report is assess if the outcomes differ between centres according to volume and heart transplantation status.

METHODS

A systematic search was performed according to PRISMA statement using PubMed/Medline databases between 2010 and 2018. Relevant articles were scrutinized and included in the meta-analysis only if reporting in-hospital/30-day mortality and heart transplantation status of the centre. Paediatric and congenital heart surgery-related studies along with those conducted in the setting of veno-venous ECMO for respiratory distress syndrome were excluded. Differences were assessed by means of subgroup meta-analysis and meta-regression.

RESULTS

Fifty-four studies enrolling N = 4421 ECMO patients were included. Of those, 6 series were performed in non-HTx centres (204 pts.;4.6%). Overall 30-day survival (95% Confidence Intervals) was 35.3% (32.5-38.2%) and did not statistically differ between non-HTx: 33.3% (26.8-40.4%) and HTx centres: 35.7% (32.7-38.8%); Pinteraction = 0.531. There was no impact of centre volume on survival as well: ßcoef = 0.0006; P = 0.833. No statistical differences were seen between HTx and non-HTx with respect to ECMO duration, limb complications, reoperations for bleeding, kidney injury and sepsis. There were however significantly less neurological complications in the HTx as compared to non-HTx centres: 11.9% vs 19.5% respectively; P = 0.009; an inverse relationship was seen for neurologic complications in centres performing more ECMOs annually ßcoef = - 0.0066; P = 0.031. Weaning rates and bridging to HTx and/or VADs were higher in HTx facilities.

CONCLUSIONS

There was no apparent difference in survival after ECMO implantation for refractory PCS according to centre's ECMO volume and transplantation status. Potentially different risk profiles of patients in these centres must be taken account for before definite conclusions are drawn.

Structured review of post-cardiotomy extracorporeal membrane oxygenation: part 1-Adult patients

Cardiogenic shock, cardiac arrest, acute respiratory failure, or a combination of such events, are all potential complications after cardiac surgery which lead to high mortality. Use of extracorporeal temporary cardio-circulatory and respiratory support for progressive clinical deterioration can facilitate bridging the patient to recovery or to more durable support. Over the last decade, extracorporeal membrane oxygenation (ECMO) has emerged as the preferred temporary artificial support system in such circumstances. Many factors have contributed to widespread ECMO use, including the relative ease of implantation, effectiveness, versatility, low cost relative to alternative devices, and potential for full, not just partial circulatory support. While there have been numerous publications detailing the short and midterm outcomes of ECMO support, specific reports about post-cardiotomy ECMO (PC-ECMO), are limited, single-center experiences. Etiology of cardiorespiratory failure leading to ECMO implantation, associated ECMO complications, and overall patient outcomes may be unique to the PC-ECMO population. Despite the rise in PC-ECMO use over the past decade, short-term survival has not improved. This report, therefore, aims to present a comprehensive overview of the literature with respect to the prevalence of ECMO use, patient characteristics, ECMO management, and in-hospital and early post-discharge patient outcomes for those treated for post-cardiotomy heart, lung, or heart-lung failure.

Surgical ablation for atrial fibrillation during isolated coronary artery bypass surgery

OBJECTIVES

Our goal was to evaluate early sequelae and long-term survival in patients undergoing isolated coronary artery bypass grafting (CABG) with concomitant surgical ablation for atrial fibrillation (AF).

METHODS

Procedural data from KROK (Polish National Registry of Cardiac Surgery Procedures) were collected. A total of 7879 patients with underlying AF underwent isolated CABG between 2006 and 2018 in 37 reference centres across Poland. The mean follow-up was 4.7 ± 3.5 years [median (interquartile range) 4.3 (1.7–7.4)]. Propensity score matching and Cox proportional hazards models were used to compare isolated CABG + ablation with isolated CABG.

RESULTS

Of the included patients, 346 (4.39%) underwent surgical ablation. Patients in this group were significantly younger (66.4 ± 7.5 vs 69.2 ± 8.2; P < 0.001) but had a non-significant, different baseline surgical risk (EuroSCORE: 2.11 vs 2.50; P = 0.088). After a rigorous 1:3 propensity matching (LOGIT model: 306 cases of isolated CABG + ablation vs 918 of isolated CABG alone), surgical ablation was associated with a lower 30-day risk of death [risk ratio 0.37, 95% confidence interval (CI) 0.15–0.91; P = 0.032] and multiorgan failure (risk ratio 0.29, 95% CI 0.10–0.94; P = 0.029). In the long term, surgical ablation was associated with a significant 33% improved overall survival rate: hazard ratio 0.67, 95% CI 0.49–0.90; P = 0.008. The benefit of ablation was sustained in the subgroups but was most pronounced in lower risk older patients (age >70 years, P = 0.020; elective status, P = 0.011) with 3-vessel disease (P = 0.036), history of a cerebrovascular accident (P = 0.018) and preserved left ventricular function [left ventricular ejection fraction >50%; P = 0.017; no signs of heart failure (per New York Heart Association functional class); P = 0.001] and those undergoing on-pump CABG (P < 0.001).

CONCLUSION

Surgical ablation for AF in patients undergoing isolated CABG is safe and associated with significantly improved long-term survival.

In‑hospital outcomes of rotational versus orbital atherectomy during percutaneous coronary intervention: a meta‑analysis

BACKGROUND

Data comparing rotational atherectomy (RA) with orbital atherectomy (OA) for calcified lesions is inconclusive and based on single observational studies in populations with limited numbers of patients.

AIMS

The aim of the study was to perform a meta‑analysis of observational studies comparing RA with OA for calcified lesions prior to percutaneous coronary intervention.

METHODS

Electronic databases were searched for studies comparing short‑term outcomes of RA with OA prior to percutaneous coronary intervention. Risk ratios (RRs) or mean differences (MD) and 95% confidence intervals (CIs) were calculated using a random‑effects model.

RESULTS

Meta‑analysis included 6 retrospective studies with 1590 patients treated with RA and 721 with OA. The latter was associated with shorter fluoroscopy time (MD, -3.40 min; 95% CI, -4.76 to -2.04; P <0.001, I2 = 0%), but contrast use was similar (MD, -2.78 ml; 95% CI, -16.04 to 10.47; P = 0.68; I2 = 67%). Although coronary dissection occurred 4‑fold more frequently with OA (RR, 3.87; 95% CI, 1.37-10.93; P = 0.01; I2 = 0%), perforations (RR, 2.73; 95% CI, 0.46-16.30, P = 0.27; I2 = 41), tamponade (RR, 1.78; 95% CI, 0.37-8.58; P = 0.47; I2 = 0%), and slow or no‑reflow phenomenon (RR, 0.81; 95% CI, 0.35-1.84; P = 0.61; I2 = 0%) occurred with similar frequency. The risk of 30‑day or in‑hospital myocardial infarction was lower in OA as compared with RA (RR, 0.67; 95% CI, 0.47-0.94; P = 0.02; I2 = 0%), yet the risk of in‑hospital mortality (RR, 0.73; 95% CI, 0.11-4.64; P = 0.74; I2 = 43%) and length of stay (MD, -0.27 days; 95% CI, -0.76 to -0.23; P = 0.29; I2 = 0%) did not differ.

CONCLUSIONS

Orbital atherectomy was associated with a lower risk of early myocardial infarction. However, a higher rate of coronary dissections produced by OA did not translate into increased risk of perforations, slow or no‑reflow phenomenon, or in‑hospital mortality.

Baseline surgical status and short-term mortality after extracorporeal membrane oxygenation for post-cardiotomy shock: a meta-analysis

OBJECTIVE

While reported mortality rates on post-cardiotomy extracorporeal membrane oxygenation vary from center to center, impact of baseline surgical status (elective/urgent/emergency/salvage) on mortality is still unknown.

METHODS

A systematic search was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement using PubMed/Medline databases until March 2018 using the keywords "postcardiotomy," "cardiogenic shock," "extracorporeal membrane oxygenation," and "extracorporeal life support." Relevant articles were scrutinized and included in the meta-analysis only if reporting in-hospital/30-day mortality and baseline surgical status. The correlations between mortality and percentage of elective/urgent/emergency cases were investigated. Inference analysis of baseline status and extracorporeal membrane oxygenation complications was conducted as well.

RESULTS

Twenty-two studies (conducted between 1993 and 2017) enrolling N = 2,235 post-cardiotomy extracorporeal membrane oxygenation patients were found. Patients were mostly of non-emergency status (65.2%). Overall in-hospital/30-day mortality event rate (95% confidence intervals) was 66.7% (63.3-69.9%). There were no differences in in-hospital/30-day mortality with respect to baseline surgical status in the subgroup analysis (test for subgroup differences; p = 0.406). Similarly, no differences between mortality in studies enrolling <50 versus ⩾50% of emergency/salvage cases was found: respective event rates were 66.9% (63.1-70.4%) versus 64.4% (57.3-70.8%); p = 0.525. Yet, there was a significant positive association between increasing percentage of emergency/salvage cases and rates of neurological complications (p < 0.001), limb complications (p < 0.001), and bleeding (p = 0.051). Incidence of brain death (p = 0.099) and sepsis (p = 0.134) was increased as well.

CONCLUSION

Other factors than baseline surgical status may, to a higher degree, influence the mortality in patients treated with extracorporeal membrane oxygenation for post-cardiotomy cardiogenic shock. Baseline status, however, strongly influences the complication occurrence while on extracorporeal membrane oxygenation.

Durability of Mitral Valve Bioprostheses: A Meta-Analysis of Long-Term Follow-up Studies

BACKGROUND

Porcine and pericardial valves exhibited similar freedom from structural valve deterioration after aortic valve replacement. Limited data exist regarding their durability at long-term follow-up in the mitral position.

METHODS

A literature search was performed through online databases. Papers reporting freedom from tissue valve deterioration after mitral valve replacement with a follow-up longer than 5 years were retrieved. Four porcine valves (Carpentier-Edwards [Edwards Lifesciences, Irvine, CA] and Hancock, Hancock II, and Mosaic [Medtronic, Inc, Minneapolis, MN]) and 1 pericardial prosthesis (Carpentier-Edwards) were the objects of the study. The structural valve deterioration (SVD) rate per year was calculated for each type of prosthesis. Kaplan-Meier curves and log-rank test analysis were performed to compare the long-term durability of porcine and pericardial valves.

RESULTS

Forty full-text papers including more than 15,000 patients were considered for the meta-analysis. Porcine valves were generally implanted in younger patients in the first period after their introduction. The mean age of the patients receiving a mitral bioprosthesis increased from 50 to 70 years over the decades. In patients operated after 1980 who had similar mean age at the time of implant, freedom from SVD was higher in the group of porcine valves with Mosaic prosthesis, showing the lowest rate of SVD. Long-term survival was higher for Mosaic porcine and Carpentier pericardial valves.

CONCLUSIONS

In surgical populations that underwent mitral valve replacement after 1980 with new generation tissue valves and similar mean age at the implant time, we found, at long-term follow-up, a higher freedom from SVD in the group of porcine prostheses.

Structured review of post-cardiotomy extracorporeal membrane oxygenation: Part 2-pediatric patients

Veno-arterial extracorporeal membrane oxygenation (ECMO) is established therapy for short-term circulatory support for children with life-treating cardiorespiratory dysfunction. In children with congenital heart disease (CHD), ECMO is commonly used to support patients with post-cardiotomy shock or complications including intractable arrhythmias, cardiac arrest, and acute respiratory failure. Cannulation configurations include central, when the right atrium and aorta are utilized in patients with recent sternotomy, or peripheral, when cannulation of the neck or femoral vessels are used in non-operative patients. ECMO can be used to support any form of cardiac disease, including univentricular palliated circulation. Although veno-arterial ECMO is commonly used to support children with CHD, veno-venous ECMO has been used in selected patients with hypoxemia or ventilatory failure in the presence of good cardiac function. ECMO use and outcomes in the CHD population are mainly informed by single-center studies and reports from collated registry data. Significant knowledge gaps remain, including optimal patient selection, timing of ECMO deployment, duration of support, anti-coagulation, complications, and the impact of these factors on short- and long-term outcomes. This report, therefore, aims to present a comprehensive overview of the available literature informing patient selection, ECMO management, and in-hospital and early post-discharge outcomes in pediatric patients treated with ECMO for post-cardiotomy cardiorespiratory failure.

Transcathether aortic valve implantation with the new repositionable self-expandable Medtronic Evolut R vs. CoreValve system: evidence on the benefit of a meta-analytical approach

AIMS

To compare transcatheter aortic valve replacement TAVR with self-expandable first-generation Medtronic CoreValve with new-generation Evolut R devices in patients with aortic stenosis.

METHODS

Multiple databases were screened for all available reports directly or indirectly comparing CoreValve vs Evolut R. Primary endpoint was device success. Procedural, functional and clinical outcomes were assessed as well.

RESULTS

Ten retrospective series including 12 294 pts. were found. Overall device success rate was 95.5% and was statistically higher in the Evolut R treated patients as compared with CoreValve: 96.6 vs. 94.8%, respectively; RR (risk ratio) 95%CIs (confidence intervals): 1.02 (1.00-1.04); P = 0.01. There were no statistical differences with regard to postoperative mean aortic gradients 8.5 +/- 5.3 vs 7.9 +/- 4.6 with Evolut R and CoreValve. Evolut R valve demonstrated nearly 50% reduction of the risk for moderate-to-severe paravalvilar leak 0.55 (0.39-0.79); P = 0.001; 60% statistically significant lower risk of developing myocardial injury 0.40 (0.22-0.72); P = 0.002 and numerical reductions in the risk of acute kidney injury, vascular complications and bleeding. Together with significantly reduced risk of permanent pacemaker implantation (0.80 [0.67-0.96]; P = 0.02) the above benefits were associated with 40% reduction in the risk of 30-day all-cause mortality with Evolut R as compared to CoreValve: 0.60 (0.37-1.00); P = 0.05.

CONCLUSIONS

The use of new-generation Evolut R was associated with improved procedural, functional and clinical outcomes compared with the CoreValve device.

Three-vessel coronary artery disease may predict changes in biochemical brain injury markers after off-pump coronary artery bypass grafting. J Zhejiang Univ Sci B 2019;19:735-738. [PMID: 30178640 PMCID: PMC6137419 DOI: 10.1631/jzus.b1700553]

Neurological injury is a frequent and important complication of coronary artery bypass grafting (CABG). Several risk factors for this type of sequela have been identified, among them aortic arch atherosclerosis. Our previous study indicated that atherosclerotic burden in coronary arteries may likewise predict postoperative neurological complications (Pawliszak et al., 2016b). We assessed the severity of this condition by using the SYNTAX score calculator. However, diagnosing angiographic three-vessel coronary artery disease (3VD) could be an even simpler method of achieving this goal.

In-hospital outcomes after emergency or prophylactic veno-arterial extracorporeal membrane oxygenation during transcatheter aortic valve implantation: a comprehensive review of the literature

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) has been used to deal with life-threatening complications as well as back-up or active cardiovascular support during high-risk procedures in patients undergoing transcatheter aortic valve implantation (TAVI). PubMed and MEDLINE electronic databases were searched in order to identify studies with emergency or prophylactic V-A ECMO application in association with TAVI procedures. From November 2012 to November 2017, 14 relevant studies were identified that included 5,115 TAVI patients of whom 102 (2%) required V-A ECMO (22 prophylactically, 66 as an emergency and 14 without a reported indication). The reason for emergency V-A ECMO institution was detailed in 64 patients: left ventricle free wall rupture (n = 14), haemodynamic instability (n = 12), ventricular arrhythmias (n = 7), aortic annulus rupture (n = 6), coronary obstruction (n = 6), low left ventricular output (ejection fraction <35%) (n = 5), uncontrollable bleeding (n = 5), severe aortic regurgitation (n = 4), prosthesis embolisation (n = 3), aortic dissection (n = 1) and respiratory failure (n = 1). Femoral arterial and vein cannulation was the most common access technique for V-A ECMO institution. Major bleeding (n = 7) and vascular access complications (n = 7) were reported after ECMO institution. The overall in-hospital survival was 73% (61% in the emergency vs. 100% in the prophylactic group). V-A ECMO support should be available at any centre performing TAVI and provides effective mechanical circulatory support in an emergency setting. We present an algorithm to aid decisions about prophylactic circulatory assistance with V-A ECMO and it should form part of the heart team discussion before a TAVI procedure is undertaken.

Long-term survival and major outcomes in post-cardiotomy extracorporeal membrane oxygenation for adult patients in cardiogenic shock

Extracorporeal membrane oxygenation (ECMO) in the veno-arterial (VA) configuration is an established method for the treatment of refractory cardiogenic shock. Such a condition characterizes the postoperative course of approximatively 1% of cardiac surgery patients. Although some studies have reported ECMO-related short-term results, little is known about the long-term outcomes of VA-ECMO therapy in the post-cardiotomy setting. Therefore, an extensive literature search was conducted regarding articles published after 1990 reporting postoperative ECMO use. PubMed, EMBASE and Web of Science were searched for sources. In-hospital mortality was high in post-cardiotomy VA-ECMO patients, ranging from 24.8% to 52%. Long-term results were poorly reported. However, based on the limited information available, hospital survivors showed a favorable outcome, with improvement in overall clinical condition, quality of life and limited hospital readmission for cardiac-related events. To conclude, in-hospital outcome in post-cardiotomy ECMO is often unfavorable, post-discharge results show satisfactory condition, with stable improvement of overall patient clinical status and low rate of hospital readmission and cardiac-related adverse events. Data reporting is, however, scarce and hence new and detailed studies are still warranted to investigate such aspects.

Clinical complications during veno-arterial extracorporeal membrane oxigenation in post-cardiotomy and non post-cardiotomy shock: still the achille's heel

Extracorporeal membrane oxygenation (ECMO) is life-saving for potentially reversible heart failure and respiratory injuries not responsive to conventional therapies. Technological innovations have produced over the years significant improvements in ECMO devices (pump, cannula design and oxygenator) and have allowed a better risk/benefit profile. Alongside with recognized advantages in the treatment of very sick patients, ECMO remains an invasive procedure for mechanical circulatory support (MCS) and it is associated with complications that strongly influence the prognosis. Current review was designed to provide a comprehensive outline on ECMO complications, analyzing risk factors and strategies of management, focusing on adult population undergoing veno-arterial ECMO (VA-ECMO) therapy.

Association Between Baseline LDL-C Level and Total and Cardiovascular Mortality After LDL-C Lowering: A Systematic Review and Meta-analysis

IMPORTANCE

Effects on specific fatal and nonfatal end points appear to vary for low-density lipoprotein cholesterol (LDL-C)-lowering drug trials.

OBJECTIVE

To evaluate whether baseline LDL-C level is associated with total and cardiovascular mortality risk reductions.

DATA SOURCESAND STUDY SELECTION

Electronic databases (Cochrane, MEDLINE, EMBASE, TCTMD, ClinicalTrials.gov, major congress proceedings) were searched through February 2, 2018, to identify randomized clinical trials of statins, ezetimibe, and PCSK9-inhibiting monoclonal antibodies.

DATA EXTRACTION AND SYNTHESIS

Two investigators abstracted data and appraised risks of bias. Intervention groups were categorized as "more intensive" (more potent pharmacologic intervention) or "less intensive" (less potent, placebo, or control group).

MAIN OUTCOMES AND MEASURES

The coprimary end points were total mortality and cardiovascular mortality. Random-effects meta-regression and meta-analyses evaluated associations between baseline LDL-C level and reductions in mortality end points and secondary end points including major adverse cardiac events (MACE).

RESULTS

In 34 trials, 136 299 patients received more intensive and 133 989 received less intensive LDL-C lowering. All-cause mortality was lower for more vs less intensive therapy (7.08% vs 7.70%; rate ratio [RR], 0.92 [95% CI, 0.88 to 0.96]), but varied by baseline LDL-C level. Meta-regression showed more intensive LDL-C lowering was associated with greater reductions in all-cause mortality with higher baseline LDL-C levels (change in RRs per 40-mg/dL increase in baseline LDL-C, 0.91 [95% CI, 0.86 to 0.96]; P = .001; absolute risk difference [ARD], -1.05 incident cases per 1000 person-years [95% CI, -1.59 to -0.51]), but only when baseline LDL-C levels were 100 mg/dL or greater (P < .001 for interaction) in a meta-analysis. Cardiovascular mortality was lower for more vs less intensive therapy (3.48% vs 4.07%; RR, 0.84 [95% CI, 0.79 to 0.89]) but varied by baseline LDL-C level. Meta-regression showed more intensive LDL-C lowering was associated with a greater reduction in cardiovascular mortality with higher baseline LDL-C levels (change in RRs per 40-mg/dL increase in baseline LDL-C, 0.86 [95% CI, 0.80 to 0.94]; P < .001; ARD, -1.0 incident cases per 1000 person-years [95% CI, -1.51 to -0.45]), but only when baseline LDL-C levels were 100 mg/dL or greater (P < .001 for interaction) in a meta-analysis. Trials with baseline LDL-C levels of 160 mg/dL or greater had the greatest reduction in all-cause mortality (RR, 0.72 [95% CI, 0.62 to 0.84]; P < .001; 4.3 fewer deaths per 1000 person-years) in a meta-analysis. More intensive LDL-C lowering was also associated with progressively greater risk reductions with higher baseline LDL-C level for myocardial infarction, revascularization, and MACE.

CONCLUSIONS AND RELEVANCE

In these meta-analyses and meta-regressions, more intensive compared with less intensive LDL-C lowering was associated with a greater reduction in risk of total and cardiovascular mortality in trials of patients with higher baseline LDL-C levels. This association was not present when baseline LDL-C level was less than 100 mg/dL, suggesting that the greatest benefit from LDL-C-lowering therapy may occur for patients with higher baseline LDL-C levels.