Angioplasty of a Severely Calcified RCA in a Patient with a History of CABG

Dr. Piotr Kałmucki

Poznań. Poland

Introduction

This case describes the angioplasty of a severely calcified subtotal occlusion in a dominant right coronary artery (RCA) in a patient with a history of coronary artery bypass grafting (CABG), who presented with a non-ST elevation myocardial infarction (NSTEMI).
Calcified lesions remain one of the greatest challenges in percutaneous coronary interventions (PCI). These procedures often require various plaque modification techniques, such as cutting balloons, rotablation, orbital atherectomy, or intravascular lithotripsy, along with the use of microcatheters. Microcatheters allow for guidewire exchange and selective contrast injection, facilitating safe crossing of complex lesions and, in many cases, serving as the only option to position a guidewire safely in the distal coronary artery segment.

Patient Profile

64-year-old woman with a history of CABG in 2010 (LIMA-LAD, vein graft to diagonal, vein graft to marginal).
Admitted for NSTEMI with recurrent chest pain, ischemic changes on ECG, and elevated troponins.
Medical history: Paroxysmal atrial fibrillation, subdural hematoma, failed left atrial appendage closure (April 2023), hypertension, and hyperlipidaemia.
Initial Coronary Angiography Findings:
- Left main coronary artery (LMCA) stenosis.
- Occlusion of the LAD and LIMA-LAD graft.
- Patent vein grafts to the obtuse marginal and diagonal branches.
- Severely calcified subtotal occlusion of the RCA, with competitive filling from the left coronary artery.
A decision was made to perform PCI on the RCA.

Lesion Type

Severely calcified subtotal occlusion in a dominant RCA, without prior graft.
Difficult anatomical visualization due to contralateral filling.
Challenges in guidewire crossing and rotablation wire delivery.

Procedure

The PCI was performed via right and left radial access. Three main challenges were identified:

Lesion Visualization: Due to complex anatomy, selective injections with the Navitian microcatheter were performed to delineate the RCA and identify a suitable channel for guidewire crossing.
Crossing the Lesion: The Navitian microcatheter was used to facilitate hydrophilic guidewire exchange, allowing successful crossing with a Fielder XT-R guidewire.
Rotablation and Stent Placement:
- Pre-dilation with multiple balloons and guide extension support.
- The Navitian microcatheter was advanced distally to ensure safe placement of the rotablation guidewire.
- Rotablation was performed with a 1.5 mm burr along the entire RCA length.
- The rotablation wire was exchanged using the trapping technique to introduce a support wire for PCI.
- Three drug-eluting stents (DES) were implanted:
  - Distal RCA: Angiolite 2.5x44 mm, post-dilated with NC 3.0 mm balloon.
  - Mid RCA: Angiolite 3.0x44 mm, post-dilated with NC 3.0 and 3.5 mm balloons.
  - Proximal RCA: Ultimaster 3.5x38 mm, post-dilated with NC 3.75 mm balloon.

Results

Final TIMI 3 flows without immediate complications.
Procedure duration: 165 minutes, contrast volume: 200 mL, radiation dose: 990 mGy.
Post-procedure haemoglobin drop due to gastrointestinal bleeding from a peptic ulcer, successfully treated via endoscopy.
Favourable clinical evolution and hospital discharge.

Conclusion

The use of the Navitian microcatheter was crucial in key stages of the PCI, improving the safety and efficacy of the procedure. Its use enabled anatomical visualization through selective injection, safe guidewire exchange for lesion crossing, distal placement of the rotablation wire, and final exchange for a PCI support wire, facilitating the successful treatment of a complex calcified lesion in the RCA.

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