Antiplatelet Therapy in Acute Myocardial Infarction and Cardiogenic Shock: Insights From the National Cardiogenic Shock Initiative

BACKGROUND

Patients presenting with acute myocardial infarction complicated by cardiogenic shock (AMI-CS) are at high risk for impaired antiplatelet activity secondary to malabsorption, systemic hypoperfusion, hypothermia, need for mechanical ventilation, and high use of analgesics. The use of antiplatelet therapy in these high-risk patients is not well studied.

METHODS

Using the National Cardiogenic Shock Initiative database, we analyzed patients who presented with AMI-CS at 60 hospitals from March 2018 to December 2020. All patients were treated using a standard shock protocol. Herein, the patterns of antiplatelet use are described.

RESULTS

A total of 204 patients were included in the analysis, of which 174 (85.3%) presented with ST-segment elevation myocardial infarction (STEMI). The majority (84.3%) received antiplatelet therapy before percutaneous coronary intervention (PCI); of those who received antiplatelets, 77.9% received aspirin, 55.2% received an oral P2Y12 inhibitor, and 19.2% received intravenous (IV) antiplatelet therapy. Ticagrelor was the most common P2Y12 inhibitor administered (41.9%), followed by clopidogrel (12.2%) and prasugrel (1.2%). Only 18.6% of oral antiplatelet agents were crushed. Baseline characteristics of patients who received IV vs non-IV antiplatelet agents were similar. Thrombolysis in Myocardial Infarction (TIMI) 0 flow was present in 69.6% of patients before PCI and aspiration thrombectomy was performed in 24.5% of patients. The presence of STEMI, cardiac arrest, cardiopulmonary resuscitation, hypothermia, vasopressor use, elevated lactate levels, or number of vessels treated did not influence the use of IV antiplatelet agents.

CONCLUSIONS

The use of crushed and IV antiplatelet agents in AMI-CS is low. Further studies are needed in this high-risk population to assess whether more potent antiplatelet inhibition will improve outcomes.

Clinical features and outcomes in patients with cardiogenic shock complicating acute myocardial infarction: early vs recent experience with impella

OBJECTIVES

To compare clinical features and outcomes in patients with acute myocardial infarction complicated by cardiogenic shock (AMICS) treated in the early experience with Impella percutaneous ventricular assist device and patients treated recently.

BACKGROUND

Since pre-market approval (PMA) of Impella device as treatment for AMICS, use of the device has grown considerably.

METHODS

We retrospectively analyzed 649 AMICS patients treated with perioperative Impella, with 291 patients treated from 2008 to 2014 comprising the early experience cohort and 358 patients treated from 2017 to 2019 comprising the recent experience cohort. The primary end point was risk adjusted in-hospital mortality.

RESULTS

Mean age and gender distribution of patients was similar in the two cohorts. The recent cohort had more invasive hemodynamic monitoring (64% vs 46%; P < .001) and less use of an intra-aortic balloon pump prior to Impella (15% vs 41%; P < .001). Recently treated patients were significantly more likely to receive Impella support prior to PCI (58% vs 44%; P = .005). In-hospital mortality was lower in the recent cohort (48% vs 56%; P = .043). This difference was however no longer significant after risk adjustment (adjusted OR 0.89, 95% CI 0.59-1.34, P = .59). Rates of acute kidney injury, major bleeding, and vascular complications requiring surgery were also significantly lower in the recent cohort.

CONCLUSIONS

Use of Impella for AMICS during recent years is associated with lower unadjusted in-hospital mortality, which may reflect better patient selection, earlier device implantation, and improved management algorithms. In-depth understanding of these factors may inform the development of future treatment protocols.

Association of Operator and Hospital Experience With Procedural Success Rates and Outcomes in Patients Undergoing Percutaneous Coronary Interventions for Chronic Total Occlusions

Background:

An inverse relationship has been described between procedural success and outcomes of all major cardiovascular procedures. However, this relationship has not been studied for percutaneous coronary intervention (PCI) of chronic total occlusion (CTO).

Methods:

We analyzed the data on patients enrolled in Blue Cross Blue Shield of Michigan Cardiovascular Consortium registry in Michigan (January 1, 2010 to March 31, 2018) to evaluate the association of operator and hospital experience with procedural success and outcomes of patients undergoing CTO-PCI. CTO-PCI was defined as intervention of a 100% occluded coronary artery presumed to be ≥3 months old.

Results:

Among 210 172 patients enrolled in the registry, 7389 (3.5%) CTO-PCIs were attempted with a success rate of 53%. CTO-PCI success increased with operator experience (45% and 65% in the lowest and highest experience tertiles) and was the highest for highly experienced operators at higher experience centers and the lowest for inexperienced operators at low experience hospitals. Multivariable logistic regression models (with spline transformed prior operator and institutional experience) demonstrated a positive relationship between prior operator and site experience and procedural success rates (likelihood ratio test=141.12, df=15, P <0.001) but no relationship between operator and site experience and major adverse cardiac event (likelihood ratio test=19.12, df=15, P =0.208).

Conclusions:

Operator and hospital CTO-PCI experiences were directly related to procedural success but were not related to major adverse cardiac event among patients undergoing CTO-PCIs. Inexperienced operators at high experience centers had significantly higher success but not major adverse cardiac event rates compared with inexperienced operators at low experience centers. These data suggested that CTO-PCI safety and success could potentially be improved by selective referral of these procedures to experienced operators working at highly experienced centers.

Unmasking Severe Tricuspid Valve Regurgitation After Percutaneous Debulking of Large Tricuspid Vegetation

A 27-year-old man admitted with tricuspid valve endocarditis with a large vegetation, persistent bacteremia, and pulmonary and systemic septic embolization was deemed not a suitable surgical candidate. He underwent percutaneous vegetation debulking using the AngioVac system. The patient defervesced post-operatively with clinical improvement but with abruptly worsened tricuspid regurgitation. (Level of Difficulty: Beginner.).

Improved Outcomes Associated with the use of Shock Protocols: Updates from the National Cardiogenic Shock Initiative

BACKGROUND

The National Cardiogenic Shock Initiative is a single-arm, prospective, multicenter study to assess outcomes associated with early mechanical circulatory support (MCS) in patients presenting with acute myocardial infarction and cardiogenic shock (AMICS) treated with percutaneous coronary intervention (PCI).

METHODS

Between July 2016 and February 2019, 35 sites participated and enrolled into the study. All centers agreed to treat patients with AMICS using a standard protocol emphasizing invasive hemodynamic monitoring and rapid initiation of MCS. Inclusion and exclusion criteria mimicked those of the "SHOCK" trial with an additional exclusion criteria of intra-aortic balloon pump counter-pulsation prior to MCS.

RESULTS

A total of 171 consecutive patients were enrolled. Patients had an average age of 63 years, 77% were male, and 68% were admitted with AMICS. About 83% of patients were on vasopressors or inotropes, 20% had a witnessed out of hospital cardiac arrest, 29% had in-hospital cardiac arrest, and 10% were under active cardiopulmonary resuscitation during MCS implantation. In accordance with the protocol, 74% of patients had MCS implanted prior to PCI. Right heart catheterization was performed in 92%. About 78% of patients presented with ST-elevation myocardial infarction with average door to support times of 85 ± 63 min and door to balloon times of 87 ± 58 min. Survival to discharge was 72%. Creatinine ≥2, lactate >4, cardiac power output (CPO) <0.6 W, and age ≥ 70 years were predictors of mortality. Lactate and CPO measurements at 12-24 hr reliably predicted overall mortality postindex procedure.

CONCLUSION

In contemporary practice, use of a shock protocol emphasizing best practices is associated with improved outcomes.

The association of race with quality of health in peripheral artery disease following peripheral vascular intervention: The Q-PAD Study

Black patients have a higher prevalence of peripheral artery disease (PAD) than white patients, and also tend to have a greater extent and severity of disease, and poorer outcomes. The association of race with quality of health (QOH) after peripheral vascular intervention (PVI), however, is less well-known. In our study, we hypothesized that after PVI, black patients experience worse QOH than white patients. We retrospectively assessed racial differences in health status using responses to the Peripheral Arterial Questionnaire (PAQ) at baseline (pre-PVI) and up to 6 months following PVI among 387 patients. We used the PAQ summary score (which includes physical limitation, symptoms, social function and quality of life) as a measure of QOH. We compared QOH scores at baseline and at follow-up after PVI between black ( n=132, 34.1%) and white ( n=255, 65.9%) patients. We then computed the change in score from baseline to follow-up for each patient (the delta) and compared the median delta between the two groups. Multivariable regression was used to model the delta QOH after controlling for factors associated with race or with the delta QOH. There was no significant difference in mean QOH by race either at baseline ( p=0.09) or at follow-up ( p=0.45). There was no significant difference in the unadjusted median delta by race (white 25.3 vs black 21.5, p=0.28) and QOH scores improved significantly at follow-up in both groups, albeit the improvement was marginally lower in black compared with white patients after adjustment for baseline confounders ( b = -6.6, p=0.05, 95% CI -13.2, -0.11).

Infrainguinal CTO Recanalization Assessed by Intravascular Ultrasound: Results of the CENTRAL Study

OBJECTIVES

CENTRAL was a prospective, multicenter, 100 patient study designed to evaluate the ability of a recanalization catheter system to cross chronic total occlusions (CTOs) of the superficial femoral artery while staying within the central vessel lumen.

METHODS

The primary endpoint was the successful crossing of a CTO (≥90% of the length) with the recanalization catheter in the central lumen of the superficial femoral artery in at least one-half of the studied patient population, confirmed by intravascular ultrasound. Secondary endpoints included standardized anatomic damage assessment (the TAPE method) and an assessment of the relationship between the percent of CTO crossing and TAPE scores to the rate of target-lesion revascularization (TLR) at 30 days and 6 months.

RESULTS

The mean age of the occlusions was 16.6 ± 22.28 months (range, 1-120 months), the average occlusion length reported by the sites was 132.1 ± 87.69 mm (range, 4-300 mm), and a majority of lesions were moderately (42.0%) or severely (32.0%) calcified. In 43/85 (50.6%) of the evaluable intravascular ultrasound images, the recanalization catheter successfully navigated the central lumen of the CTO (ie, ≥90% luminal crossing) with >50% luminal crossing in 64/85 (75.3%) of cases. The 6-month TLR rate was significantly lower in patients where the CTO was crossed ≥90% in the central vessel lumen (4.7%) compared with crossings <90% (20.6%; P=.04). The 6-month TLR rate was 3.5% in patients with a favorable TAPE score of 0-4 and 36.8% with an unfavorable TAPE score of 5-8 (P<.001).

CONCLUSION

Use of a recanalization catheter in complex superficial femoral artery CTO crossings achieved intraluminal crossings in >50% of cases and decreased anatomic damage, which appeared to offer a significant advantage in 6-month TLR rates.

Relation of Baseline Renal Dysfunction With Outcomes in Patients Undergoing Popliteal and Infrapopliteal Percutaneous Peripheral Arterial Interventions

Renal dysfunction is a major risk factor for peripheral arterial disease (PAD). Infrapopliteal PAD is associated with more co-morbid conditions and worse prognosis than suprapopliteal PAD. Long-term outcomes of patients with renal dysfunction and popliteal or infrapopliteal PAD undergoing peripheral vascular intervention (PVI) are not well described. We retrospectively evaluated long-term outcomes in 726 patients undergoing infrapopliteal PVI categorized into 3 glomerular filtration rate (GFR)-based groups: GFR (≥60 ml/min/1.73 m(2)), GFR (<60 ml/min/1.73 m(2)), and those on dialysis. At mean follow-up of 36 ± 20 months, amputation rates were 3%, 5%, and 11% with mortality rates of 23%, 36%, and 56% in normal renal function, chronic kidney disease (adjusted odds ratio [OR] for amputation 1.75, 95% CI 0.73 to 4.21; adjusted OR for mortality 1.53, 95% CI 1.05 to 2.23, p = 0.028), and dialysis (adjusted OR for amputation 2.43, 95% CI 0.84 to 7.02, p = 0.100; adjusted OR for mortality 4.51, 95% CI 2.46 to 8.26, p <0.0001) groups, respectively. Repeat revascularization was similar in all 3 groups at roughly 25%. In conclusion, chronic kidney disease and dialysis were associated with increased major amputations and mortality in patients who received PVI for popliteal and infrapopliteal PAD.

Association Of Bleeding Avoidance Strategies with age-related bleeding and In-hospital mortality in patients undergoing percutaneous coronary Interventions

BACKGROUND

The association of bleeding avoidance strategy (BAS) (consisting of a combination of radial access, bivalirudin [rather than heparin +/- glycoprotein GPIIb/IIIa antagonists], and/or vascular closure devices after femoral access) with bleeding and in-hospital outcomes has not been evaluated among elderly patients undergoing percutaneous coronary interventions (PCI).

METHODS

We studied BAS use, bleeding and in-hospital mortality among 121,635 patients categorized by age (<50, 50-59, 60-69, 70-79, and ≥80years) undergoing PCI from the BMC2 registry (1/2010-12/2013).

RESULTS

The use of BAS decreased marginally with age and despite improved utilization over time, remained lower among the elderly. BAS was used in a much lower risk cohort among all age groups. Nonetheless, compared with no BAS, the use of this strategy was associated with lower bleeding (adjusted OR 0.984, 95% CI 0.980-0.985) and in-hospital mortality (adjusted OR 0.996, 95% CI 0.994-0.997) among all age-groups. Similar relative reduction in the risk of bleeding was observed among all age groups with BAS use with lowest risk (thus greatest absolute risk reduction given their highest risk for bleeding) for the oldest cohort.

CONCLUSIONS

BAS use decreased with age among patients undergoing PCI despite its association with lower in-hospital mortality. Although overall utilization improved over time, it still remained lower in the elderly cohort, a group likely to benefit most from it. These data identified an opportunity to design strategies to improve BAS use particularly among high-risk elderly patients undergoing PCI so as to decrease bleeding and reduce related adverse events and costs.

Using simulation for teaching femoral arterial access: A multicentric collaboration

OBJECTIVE

To assess the impact of simulation training on complications associated with femoral arterial access obtained by first year cardiology fellows.

BACKGROUND

Prior studies demonstrate a higher incidence of arterial access related complications among patients undergoing invasive cardiac procedures.

METHODS

First year cardiology fellows at four teaching hospitals in Michigan tracked their femoral access experience and any associated complications between July 2011 and June 2013. Fellows starting their academic training in July 2012 were first trained on a specially developed simulator before starting their rotation in the catheterization laboratory. The primary outcome was access proficiency, defined as five successful femoral access attempts without any complication or need to seek help from a more experienced team member.

RESULTS

A total of 1,278 femoral access attempts were made by 21 fellows in 2011-2012 compared with 869 femoral access attempts made by 21 fellows in 2012-2013. There was a lower rate of access related complications in patients undergoing access attempts by first year fellows in year 2 compared with year 1 (2.1% versus 4.5%, P = 0.003). The number of procedures to achieve procedural proficiency was significantly higher in year 1 compared with year 2 (median 20 versus 10, P = 0.007).

CONCLUSIONS

Incorporation of simulation in the training of first year fellows was associated with an improvement in proficiency and a clinically meaningful reduction in vascular complications.

Renal function-based contrast dosing to define safe limits of radiographic contrast media in patients undergoing percutaneous coronary interventions

OBJECTIVES

The aim of this study was to evaluate the association between calculated creatinine clearance (CCC)-based contrast dose and renal complications in patients undergoing percutaneous coronary interventions (PCI).

BACKGROUND

Excess volumes of contrast media are associated with renal complications in patients undergoing cardiac procedures. Because contrast media are excreted by the kidney, we hypothesized that a dose estimation on the basis of CCC would provide a simple strategy to define a safe dose of contrast media.

METHODS

We assessed the association between CCC-based contrast dose and the risk of contrast-induced nephropathy (CIN) and need for in-hospital dialysis in 58,957 patients undergoing PCI and enrolled in the BMC2 (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) registry from 2007 to 2008. Patients receiving dialysis at the time of the procedure were excluded.

RESULTS

The risk of CIN and nephropathy requiring dialysis (NRD) was directly associated with increasing contrast volume adjusted for renal function. The risk for CIN and NRD approached significance when the ratio of contrast dose/CCC exceeded 2 (adjusted odds ratio [OR] for CIN: 1.16, 95% confidence interval [CI]: 0.98 to 1.37, adjusted OR for NRD: 1.72, 95% CI: 0.9 to 3.27) and was dramatically elevated in patients exceeding a contrast to CCC ratio of 3 (adjusted OR for CIN: 1.46, 95% CI: 1.27 to 1.66, adjusted OR for NRD: 1.89, 95% CI: 1.21 to 2.94).

CONCLUSIONS

Our study supports the need for minimizing contrast dose in patients with renal dysfunction. A contrast dose on the basis of estimated renal function with a planned contrast volume restricted to less than thrice and preferably twice the CCC might be valuable in reducing the risk of CIN and NRD.

Temporal Trends, Safety, and Efficacy of Bivalirudin in Elective Percutaneous Coronary Intervention: Insights from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium

OBJECTIVE

To evaluate the safety and efficacy of bivalirudin based therapy among patients undergoing percutaneous coronary intervention (PCI) for stable coronary artery disease in a large multicenter registry.

BACKGROUND

The REPLACE I trial demonstrated the non-inferiority of a strategy of bivalirudin compared with heparin and glycoprotein (GP) IIbIIIa inhibition in patients undergoing PCI. There is a paucity of outcome data with bivalirudin use in the setting of real-world PCI practice.

METHODS

We evaluated the outcome of 11,719 patients who underwent elective PCI for stable coronary artery disease (CAD) from 2002 to 2004 in a large regional consortium, and who were treated with bivalirudin (n = 2051) or with heparin and GP IIbIIIa inhibitors (n = 9,668). The primary endpoints were transfusion and in-hospital major adverse cardiovascular events (MACE) defined as the composite of death, MI, stroke, and any coronary artery bypass grafting (CABG) or target lesion revascularization.

RESULTS

Compared with patients who received heparin plus GP IIbIIIa inhibitors, patients who received bivalirudin had a similar incidence of post-procedural MI, stroke, in-hospital death, MACE (2.88 vs. 2.48, P = 0.30), or transfusion (2.83% vs. 2.41%, P = 0.27). Patients at greater risk of bleeding were more likely to be treated with bivalirudin. After adjusting for the propensity to receive bivalirudin and for baseline co-morbidities, there was no difference in the odds of MACE or the need for transfusion between the two groups.

CONCLUSION

Compared with heparin plus GP IIbIIIa inhibition, use of bivalirudin in patients undergoing PCI for stable CAD is associated with similar ischemic and bleeding complications. Given the ease of administration and lower cost, bivalirudin provides an attractive treatment option in this patient population.

Feasibility of percutaneous coronary interventions in early postcoronary artery bypass graft occlusion or stenosis

BACKGROUND

With continuing technical advances in percutaneous coronary interventions (PCI) for coronary artery disease (CAD), patients undergoing coronary artery bypass surgery (CABG) often have complex coronary anatomy that is not ideal for PCI. Because of the complex anatomy, these patients have a higher risk of early graft occlusion. The feasibility of PCI in the treatment of early graft occlusion is not well established.

METHODS

A retrospective chart review was performed of patients presenting with recurrent ischemia within three months post-CABG and at one-year follow-up.

RESULTS

Forty-six patients with 156 grafts were identified. Three presented with STEMI, 21 with NSTEMI, 21 with unstable angina, and one with congestive heart failure. Sixty-three grafts were occluded or stenosed (>70%). Twenty-seven grafts (43%) in 17 patients were not amenable to PCI. The other 34 grafts (54%) in 23 patients underwent successful PCI. PCI was performed upon native vessels and occluded grafts with equal frequency. Six patients had patent grafts. At one-year follow-up, six of 23 patients in the PCI group were readmitted with ischemia; five vessels (14%) in four patients had restenosed. There were no deaths. In the group with no PCI, 11 of 23 patients were readmitted with ischemia with one death.

CONCLUSION

PCI for early post-CABG occlusion was safely performed in slightly more than half of target vessels. PCI was performed upon native vessels and occluded grafts with equal frequency. After initial PCI success, the clinical target vessel restenosis rate was 14% at one-year follow-up.

Relationship Between Operator Volume and Adverse Outcome in Contemporary Percutaneous Coronary Intervention Practice

OBJECTIVES

The aim of our study was to evaluate the volume-outcome relationship in a large, quality-controlled, contemporary percutaneous coronary interventions (PCI) database.

BACKGROUND

Whether the relationship between physician volume of PCI and outcomes still exists in the era of coronary stents is unclear.

METHODS

Data on 18,504 consecutive PCIs performed by 165 operators in calendar year 2002 were prospectively collected in a regional consortium. Operators' volume was divided into quintiles (1 to 33, 34 to 89, 90 to 139, 140 to 206, and 207 to 582 procedures/year). The primary end point was a composite of major adverse cardiovascular events (MACE) including death, coronary artery bypass grafting, stroke or transient ischemic attack, myocardial infarction, and repeat PCI at the same site during the index hospital stay.

RESULTS

The unadjusted MACE rate was significantly higher in quintiles one and two of operator volume when compared with quintile five (7.38% and 6.13% vs. 4.15%, p = 0.002 and p = 0.0001, respectively). A similar trend was observed for in-hospital death. After adjustment for comorbidities, patients treated by low volume operators had a 63% increased odds of MACE (adjusted odds ratio [OR] 1.63, 95% confidence interval [CI] 1.29 to 2.06, p < 0.0001 for quintile [Q]1; adjusted OR 1.63, 95% CI 1.34 to 1.90, p < 0.0001 for Q2 vs. Q5), but not of in-hospital death. Overall, high volume operators had better outcomes than low volume operators in low-risk and high-risk patients.

CONCLUSIONS

Although the relationship between operator volume and in-hospital mortality is no longer significant, the relationship between volume and any adverse outcome is still present. Technological advancements have not yet completely offset the influence of procedural volume on proficiency of PCIs.

Eptifibatide and risk of bleeding after failed thrombolysis

The safety of adjunct eptifibatide in the setting of rescue angioplasty (PTCA) with or without stenting after full-dose thrombolytic therapy is not well defined. Our study was undertaken to assess the risk of hemorrhagic complications following use of eptifibatide in patients undergoing rescue PTCA/stenting following failed thrombolysis. Clinical records of 43 consecutive patients (53% males) who received eptifibatide during rescue PTCA/stenting following full-dose fibrinolytic therapy were reviewed. Data were collected for: timing of rescue PTCA following fibrinolytic use; concomitant use of other antiplatelet agents; hospital length of stay; in-hospital mortality; and incidence of bleeding complications. Bleeding complications were categorized as major or minor according to Thrombolysis in Myocardial Infarction (TIMI) study group criteria. Overall bleeding complications developed in 13 patients (30%), with 4 patients (9%) experiencing major bleeding. Univariate predictors of major bleeding complications were: older age; female sex; lower baseline platelet count; and time to initiation of eptifibatide following failed thrombolysis. On multivariate analysis, the only predictors of bleeding were gender (27% in females versus 3% in males; odds ratio, 1.7; 95% confidence interval, 0.1-0.9) and time to initiation of eptifibatide following failed thrombolysis (4.6 +/- 2 hours versus 11 +/- 9 hours; p<0.04; 95% confidence interval, 2.1-11.4). Use of potent antiplatelet agents during rescue PTCA/stenting results in an increased risk of bleeding. Careful attention to predictors of bleeding and, in particular, delaying eptifibatide administration following full-dose fibrinolytic use may result in the reduction of major and minor bleeding complications.