Transradial Angiography and Intervention in Acute Coronary Syndromes

Elie Akl, MDa, Mohammed K. Rashid, MDa, Ahmad Alshatti, MDa, Sanjit S. Jolly, MD, MSca,b,*

 

INTRODUCTION

Transradial access (TRA) is associated with less bleeding and vascular complications than trans- femoral access (TFA) in patients with acute coro- nary syndromes (ACS).^1,2 A large body of evidence currently supports embracing TRA to improve outcomes in these patients. This is re- flected in a 2018 scientific statement from the American Heart Association in which a radial- first approach was strongly recommended in all patients undergoing cardiac  catheterization, with a graduated level of center and operator experience for TRA use in patients with ACS.³

Bleeding Is an Important Outcome in Patients with Acute Coronary Syndrome

Although advances in adjuvant pharmaco- therapy have reduced the risk of ischemic PCI- related complications, the use of antithrombotic agents, especially in the presence of an

 

arteriotomy site, increases the risk of bleeding complications. The incidence of bleeding in- creases with the acuity of clinical presentation and is higher in patients with ACS compared with those with stable coronary artery disease.⁴ Verheugt and colleagues⁵ examined the prog- nostic impact of 30-day bleeding in a combined dataset from the REPLACE 2, ACUITY, and HO- RIZONS AMI trials that included 17,393 patients with ACS undergoing PCI. The rate of access site bleeding was 2.1% and that of non–access site bleeding was 3.3%. One-year mortality was 2.54% in patients with no bleeding, 6.16% with access site bleeding (relative risk [RR], 2.33; 95% confidence interval [CI], 1.53–3.53), and 14.4% with non–access site bleeding (RR, 5.40; 95% CI, 4.32–6.74). After adjustment, the hazard ratio (HR) of non–access site bleeding was more than double that of access site bleeding (HR, 3.94; 95% CI, 3.07–5.15; P<.0001 vs HR, 1.82;

 

 

 

^a Department of Medicine, Division of Cardiology, McMaster University, Room C3-118, DBCVSRI Building, 237 Barton Street East, Hamilton, ON L8L 2X2, Canada; ^b Population Health Research Institute, Hamilton, Ontario, Canada

* Corresponding author. Hamilton General Hospital, Room C3-118, DBCVSRI Building, 237 Barton Street East, Hamilton, Ontario L8L 2X2, Canada.

E-mail address: sanjit.jolly@phri.ca

 

Intervent Cardiol Clin 9 (2020) 33–40 https://doi.org/10.1016/j.iccl.2019.08.003

2211-7458/20/ª 2019 Elsevier Inc. All rights reserved.

 

 

 

 

95% CI, 1.17–2.83; P 5 .008, respectively), but both were associated with increased mortality. These findings were subsequently corroborated in larger studies.^6,7

It is unclear whether bleeding is a marker of risk or causal for mortality. Nonetheless, several mechanisms by which bleeding may affect mor- tality have been proposed. These include pre- mature cessation of dual antiplatelet therapy, blood transfusion-related adverse affects, exag- geration of inflammatory responses, and gener- ation of a prothrombotic milieu through  activation of the coagulation cascade.⁸ Anemia itself decreases oxygen delivery, increases oxy- gen demand, and can lead to ischemic events owing to supply–demand mismatch. Regardless of the mechanisms involved, if bleeding in- creases mortality, then avoiding it should decrease mortality. Multiple strategies can be used to minimize bleeding risk in patients with ACS. Pharmacologic therapies that reduce bleeding in ACS have been associated with re- ductions in mortality (bivalirudin in HORIZONS AMI⁹ and fondaparinux in the OASIS 5 and 6 tri- als¹⁰). This finding supports the mechanism that reducing bleeding can lead to reductions in mortality.

 

RANDOMIZED CONTROLLED TRIALS OF TRANSRADIAL ACCESS VERSUS THE FEMORAL APPROACH IN PATIENTS WITH ACUTE CORONARY SYNDROME

Several large randomized trials comparing the radial versus the femoral approach in the ACS population were published over the past  decade. The RadIal vs femorAL access for coro- nary intervention (RIVAL)¹ trial randomized a to- tal of 7021 patients with ACS with or without ST- segment elevation. The primary outcome of death, myocardial infarction (MI), stroke, or non- coronary artery bypass grafting  (CABG) bleeding at 30 days occurred in 3.7%  in  the TRA group versus 4.0% in the TFA group (HR, 0.92; 95% CI, 0.72–1.17; P 5 .50). The rate of

major adverse cardiac events (MACE; composite of death, MI, and stroke) was also similar be- tween the 2 groups (3.2% vs 3.2%; HR, 0.98;

95% CI, 0.76–1.28; P 5 .90). However, many

notable findings should be underlined. First, in centers with the highest radial PCI volumes, there was a benefit with TRA over TFA for MACE, major vascular complications, and access site crossover. Second, there was a significant benefit with TRA in patients with ST-segment elevation MI (STEMI). This is detailed in a subse- quent  section.  Third,  although  major  bleeding

did not differ as per the trial-specific definition,   a post hoc analysis showed a significant reduc- tion with radial access when the ACUITY trial bleeding definition was used (P<.0001). Fourth, the rate of major vascular complications was significantly lower with the radial  approach (1.4% vs 3.7%; HR, 0.37; 95% CI, 0.27–0.52;

P<.0001). This was driven by a reduction in large

hematoma and pseudoaneurysm needing closure.

The Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of AngioX (MATRIX) was a large trial of more than 8400 patients with ACS.² The primary outcome of MACE was lower with TRA compared with TFA (8.8% vs 10.3%; RR, 0.85;

95% CI, 0.74–0.99; P 5 .0307). Similarly, the sec- ond coprimary outcome of a net adverse clinical events (NACE) was also reduced with the radial approach  (9.8% vs  11.7%;  RR,  0.83;  95% CI,

0.73–0.96; P 5 .0092). The difference was mainly driven by bleeding academic research con- sortium (BARC) major bleeding unrelated to CABG (1.6% vs 2.3%, RR, 0.67; 95% CI, 0.49–

0.92; P 5 .0128) and all-cause mortality (1.6%

vs 2.2%; RR, 0.72; 95% CI, 0.53–0.99; P 5 .045).

 

Transradial Access Versus Transfemoral Access in Patients with an ST Elevation Myocardial Infarction

In the RIVAL-STEMI subgroup of 1958 patients, MACE (HR, 0.59; 95% CI, 0.36–0.95; P 5 .031),

NACE (HR, 0.60; 95% CI, 0.38–0.94, P 5 .026),

and all-cause mortality (HR, 0.39; 95% CI, 0.20–

0.76; P 5 .006) were decreased with radial ac- cess.¹¹ ACUITY major bleeding (HR, 0.49; 95% CI, 0.28–0.84; P 5 .009) and major vascular ac- cess site complications (HR, 0.36; 95% CI, 0.19–0.70; P 5 .002) were also significantly lower in the radial group. Another subgroup analysis of the 1451 patients treated with primary PCI showed a mortality benefit with TRA (HR, 0.46; 95% CI, 0.22–0.97; P 5 .041).

TRA provided consistent benefits in patients with NSTE-ACS and STEMI at presentation in a prespecified subanalysis of the MATRIX trial.¹² Access site BARC 2 to 5 bleeding was signifi- cantly reduced in the radial  group  irrespective of ACS presentation, as well.

The Radial vs Femoral Randomized Investiga- tion in ST-Elevation Acute Coronary Syndrome (RIFLE-STEACS) trial randomized 1001 patients with STEMI undergoing primary or rescue (8%) PCI to TRA or TFA.¹³ The composite primary outcome of death, MI, stroke, target lesion revascularization,  or  non-CABG  bleeding   at 30 days was significantly lower in the TRA arm

 

 

 

 

(13.6% vs 21%; 95% CI, 2.7%–12.0%; P 5 .003).

There was also a significant reduction in cardiac mortality (5.2% vs 9.2%; 95% CI, 0.8%–7.3%;

P 5 .020). Non–CABG-related bleeding was significantly reduced with TRA (7.8% vs 12.2%, 95% CI, 2.7–12.0; P 5 .026), mainly owing to a 60% decrease in access site-related bleeding (2.6% vs 6.8%; 95% CI, 1.6%–7.0%; P 5 .002).

The ST Elevation Myocardial Infarction Treated by RADIAL or femoral approach (STEMI-RADIAL) trial included 707 patients un- dergoing primary PCI by high-volume  opera- tors experienced in both access sites.¹⁴ The composite primary end point of major bleeding and vascular access site complications at

30 days was lower with TRA (1.4% vs 7.2%;      P 5 .0001). The NACE rate was also reduced with  the  radial   approach   (4.6%   vs   11.0%; P 5 .0028). There was a nonsignificant 26% relative reduction in mortality at 30 days and 36% at 6 months with TRA.

In the most recent trial, Safety and Efficacy of Femoral Access vs Radial Access in ST-Elevation Myocardial Infarction (SAFARI-STEMI), the pri- mary outcome of death at 30 days (1.5% vs 1.3%; RR, 1.15; 95% CI, 0.58–2.30; P 5 .69),

MACE  (4% vs  3.4%; RR,  1.17; 95%  CI, 0.77–

1.79;  P  5 .45), and  major bleeding (1.1%  vs

1.3%; P 5 .74) were  all  not  different  among the 2 groups. However, the trial was stopped early, having recruited only 2292 of the original target of 4884 patients. As a result, it is likely  that SAFARI did not have sufficient power  to test the hypothesis, which makes it difficult to draw any firm conclusion. The totality of the  data shows that radial improves outcomes compared with femoral access in STEMI.

 

Meta-analysis of Randomized Trials

An updated meta-analysis of randomized trials  of TRA versus TFA in ACS with clinical outcomes available at 30 days demonstrates a trend favor- ing TRA for MACE, defined as death from any cause (or cardiac death when all-cause mortality was not available), MI or stroke (odds ratio [OR], 0.86;  95%  CI,  0.72–1.02;  P  5  .08;  I²  5 6%)

(Fig. 1).^11–17 Radial access was associated with a decreased risk of 30-day mortality (OR, 0.71; 95% CI, 0.56–0.90; P 5 .004; I² 5 0%), major

bleeding    (OR,    0.55;    95%    CI,   0.41–0.73;

P<.0001; I² 5 24%), and vascular access compli- cations (OR, 0.32; 95% CI, 0.20–0.52; P<.00001;

I² 5 0%) at 30 days. Our findings are highly consistent with prior meta-analyses.^18–22

The evidence overwhelmingly supports a radial first approach and this is reflected in guidelines from the American Heart Association,

 

the Canadian Cardiovascular Society/Canadian Association of Intervention Cardiology, and the European Society of Cardiology/European Asso- ciation for Cardio-Thoracic Surgery, which have all endorsed the radial approach as the  preferred site for PCI^3,23,24 (Table 1).

There has previously been concerns that TRA might prolong door-to-balloon times, but contemporary studies of TRA versus TFA failed to demonstrate a significant difference in these times.^1,4,13,25 Furthermore, sensitivity analysis using the mortality benefit seen in large random- ized controlled trials with TRA suggests that the small increment in door-to-balloon times is un- likely to affect clinical benefit.²⁶

Although radial adoption in  the  United  States has been not as rapid as Europe and Canada, the use of the transradial approach is growing steadily. Data from the American Col- lege of Cardiology National  Cardiovascular  data registry has documented a greater than 6-fold increase of the radial access in primary PCI between 2007 and 2011.²⁷ Although encouraging,  these   rates   remain   much lower than those reported in European coun- tries such as Sweden and the UK, which increased from 10% to 12.5% to 55% to 60% during the same period.^28,29 These numbers underline the need  for  continuing  education  for TRA.

 

TRANSRADIAL ACCESS IN RESCUE PERCUTANEOUS CORONARY INTERVENTION

Bleeding complications in with patients with STEMI who receive fibrinolysis and undergo rescue PCI are relatively common. Thus, deter- mining the optimal access approach for these patients is of particular interest.

In the RADIAL-AMI pilot randomized trial, 50 patients requiring either primary (one-third) or rescue PCI (two-thirds) were randomized to radial versus femoral access. There was a trend toward less hematoma and less hemoglobin decrease (>30 g/L) in the radial group.¹⁵ Data from the Scottish Coronary Revascularisation Register that included 4534 patients undergo- ing primary or rescue PCI between 2000 and 2009 showed a striking reduction in 30-day mortality (adjusted OR. 0.51; 95% CI, 0.04– 0.52; P<.001), greater  procedural  success, and less access site complications or bleeding with the radial approach.³⁰ The largest evalua- tion of outcomes after rescue PCI via TRA versus TFA is from the American College of Cardiology National Cardiovascular Data

Fig. 1. Forest plots of pooled estimates of (A) MACE, (B) death, (C) major bleeding, (D) stroke, and (E) vascular access complications. MACE, major adverse cardiovascular events, defined as the composite of death, MI, and stroke.

 

 

Registry.³¹ In total, 9494 patients undergoing rescue PCI between 2009 and 2013 were stud- ied. Coronary angiography was performed at a median time of 189 minutes after fibrinolytic therapy. Only 14.2% of cases were performed transradially. Rescue PCI success  rates  were high and not different between groups (96.1% radial vs  94.7%  femoral;  P  5  .06). In propensity-matched analyses, transradial rescue PCI was associated with lower bleeding rates compared with the transfemoral approach (OR, 0.67; 95% CI, 0.52–0.97; P 5 .003), but not

 

mortality (OR, 0.81; 95% CI, 0.53–1.25;

P 5 .35). The very low in-hospital mortality (1%–2%) observed in this patient group as compared with data from  all-comers  with STEMI (in-hospital mortality, 5.5%)³² could potentially explain the  inability  to  demonstrate a mortality difference with TRA.

Given the proven decrease in bleeding end points with TRA, one should expect an incre- mental benefit with radial access in patients at highest risk of bleeding, including patients with STEMI undergoing rescue PCI.

TRANSRADIAL ACCESS IN FEMALE PATIENTS WITH ACUTE CORONARY SYNDROME

Female patients with ACS are more likely than males to suffer from bleeding and vascular com- plications.^33,34 Concerns that TRA might be more challenging in females owing to smaller

radial arteries that may be more prone to spasm make sex-specific data regarding the efficacy and safety of TRA very pertinent.

Sex-based outcomes in ACS randomized to TRA versus TFA were compared in a prespeci- fied RIVAL subgroup analysis.³³ Bleeding and major vascular complications were significantly reduced with TRA in both sexes. However, the number needed to treat to prevent 1 major vascular complication was 33 in females compared with 49 for males. Crossover rates were higher with TRA compared with TFA in both women and men, but more so in women (women:  11.1%  vs  1.9%;  HR.  5.88; P<.0001;

men: 6.3% vs 1.9%; HR, 3.32; P<.0001). PCI suc-

cess rate did not differ by sex, irrespective of ac-

 

Table 1 International Society guidelines for radial access in primary PCI   Society   Year TRA in Primary PCI CCS – STEMI 2019 Strong Guidelines23 recomm- endation, moderate- quality evidence AHA – Scientific Statement3 2018 Strong recomm- endation ESC/EACTS 2018 Class I indication Guidelines on Myocardial Revascularization24

cess site (female: HR, 1.05, P 5 .471; male: HR,

Abbreviations: AHA, American Heart Association; CCS, Canadian Cardiovascular Society; EACTS, European Asso- ciation for cardio-thoracic surgery; ESC, European Society of cardiology.

• ; P 5 .888; P_int 5 .674). When asked about their access preference for a hypothetical repeat procedure, 1% of females with TRA preferred TRA, whereas only 50.1% of females with TFA preferred TFA (P<.001).

In an analysis of the MATRIX trial,³⁴ when comparing TRA versus TFA between females and males with ACS, major adverse cardiovascu- lar and cerebrovascular events, and NACE were significantly lower with TRA in females (major adverse cardiovascular and cerebrovascular events: 9.1% vs 12.2%; RR, 0.73; 95% CI, 0.56–

0.95;  P  5 .019;  NACE:  10.4%  vs  13.9%; RR,

0.73; 95% CI, 0.56–0.93; P 5 .012), but these re-

ductions  only  trended  favorably  for  radial  in

 

Table 2 TRA versus TFA in females versus males TRA vs TFA in Females TRA vs TFA in Males Vascular complications YY Y Bleeding YY Y Crossover [[ [ PCI success 5 5 MACE Y Y/5

bleeding and access site vascular complica- tions. Patients undergoing invasive treatment for ACS are at greatest risk of bleeding and have the most to gain. The benefits of TRA have been demonstrated across the ACS spec- trum and in both sexes. A radial-first strategy should be the default approach in the ACS  population and continuous efforts should be made to increase operator expertise of TRA in these patients.

 

Abbreviation: MACCE, major adverse cardiovascular and cerebrovascular event.

 

males. BARC type 3 or 5 bleeding (P_int 5 .45) and all-cause mortality (P_int 5 0.79) were lower with TRA in both sexes.

SAFE-PCI for Women is the first randomized trial of PCI strategies performed solely in women. It differs from the above-mentioned studies in that it focused on  elective referrals  for angiography and PCI, and excluded patients with STEMI.³⁵ A total of 1787 female patients were randomized to TRA versus TFA, with 691 undergoing PCI. Unfortunately, the trial was stopped prematurely owing to a lower than ex- pected event rate. There was a significant reduc- tion in bleeding and vascular complications with TRA in the overall population (0.6% vs 1.7%; OR, 0.32; 95% CI, 0.12–0.90). There was only a trend toward benefit in the PCI group, most likely owing to the small sample size. Crossover rates were significantly higher with TRA compared with TFA (6.7% vs 1.9%; OR, 3.70; 95% CI,

2.14–6.40). Compared with women assigned to TFA, more women assigned to TRA preferred the same access route for their next procedure (71.9% vs 23.5%).

TRA is effective at significantly reducing bleeding, major vascular complications and MACE in women with similar PCI success rates compared with TFA (Table 2). The radial-first approach is especially applicable to female pa- tients who are at increased baseline risk of bleeding and vascular complications. Contin- uous efforts should be made to overcome the technical challenges with TRA in females, including gaining expertise in the use of 4F or 5F catheters to minimize the risk of spasm.

 

SUMMARY

Considerable evidence supports TRA for angi- ography and  intervention  in  patients  with  ACS, with an emphasis on decreasing major

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