Just another Type A stenosis? – When things went wrong

Iatrogenic coronary artery dissection (ICAD) is a rare but potentially life-threatening complication. Its incidence ranges only between 0.07%–0.1% and can result in death and long-lasting impairment of cardiac function. Percutaneous mechanical support can be helpful in severe cases of cardiogenic shock (CS) to treat the lesions in a more stress-free situation. Intravascular ultrasound (IVUS) can be crucial to identify correct guide-wire positioning and avoid contrast agent injections.

We present a case of a 75-year-old female patient with chest pain (CCS II-III) and typical cardiovascular risk factors who underwent elective coronary angiography (CA). The echocardiography was normal. The CA showed a 1 vessel disease with an 70% Type A stenosis in the left anterior descending artery (LAD) (Fig.1). After balloon angioplasty with a semi-compliant 2.5x12mm balloon in the left anterior oblique (LAO) angulation a dissection appeared which was believed only to be locally (Fig.2). For sealing a 2.5x20mm drug eluting stent (DES) was used. The right anterior oblique (RAO) projection showed a complete dissection of the LAD, left main (LM) and LCX with TIMI I-II flow in proximal LAD and LCX (Fig. 3), following stenting (4.0x20mm) of the medial LAD. Meanwhile the patient developed CS due to total occlusion of the LAD (Fig. 4) with ventricular fibrillation and cardiac arrest. For hemodynamical stabilization insertion of the Impella CP (Abiomed, Aachen) via right femoral artery was done. To reestablish coronary artery flow a 3.5x32mm DES was placed in the proximal LAD and a 5.0x22mm DES was used to protect the LM (Fig. 5). Before stenting of the LCX, IVUS showed a sub intimal positioning of the guidewire (Fig. 6). After correcting the guidewire position a 2.75x38mm DES was used in the medial LCX. The bifurcation of LM/LAD/LCX was done by double kiss culottes technique using a 4.0x20mm DES (Fig. 7). IVUS control showed a good result after stenting. The Impella device was removed two days later and the coronaries were patent in the main vessels but with remaining dissections in the side branches which were treated conservatively (Fig 8). The patient went to rehabilitation after two weeks of ICU treatment with no change in left ventricular ejection fraction.

A prudent catheterization technique with a cautiously use of catheter material is critical in avoiding ICAD. This includes correctly obtained images with a clear visibility of the tip of the catheter and the guidewire as well as an avoidance of non-coaxial alignment of the catheter. In this case the tip of the catheter was not visible during initial stenting and the intubation angle in the LM was steep. So the dissection was initially believed to be related to the first dilation and not in the LM. Due to the misinformation contrast agent was admitted repeatedly which worsened the situation leading to a Type F dissection. The Society for Cardiovascular Angiography and Interventions (SCAI) recommend the use of an alternative method to guide the intervention once the dissection is noted (e.g., IVUS). In cases of circulatory instability stenting the LM first is recommended. In this case the CS was rapidly progressing, so we chose to first place the Impella device to gain time for the intervention with IVUS. Key points in this case were the need of a meticulous catheterization technique and in case of an ICAD the “do no further harm” policy in combination with alternative methods to guide the intervention.

Fig. 1: Initial angiography of LAD in LAO/CRAN. 

Fig.2: Angiography of dissected LAD. Dissection membrane marked with red dots. 

 

Fig. 3: LM/LAD/LCX with dissection membrane (red dotted line) and LAD stent (green line). 

Fig. 4: Total occlusion of LAD (medial and distal stent with green lines). Dissection membrane with red dots. Note the ECG.

Fig. 5: LM and LAD after stenting (green line), dissected LCX (red dotted line) and inserted Impella device (yellow line). 

 

Fig. 6: IVUS of LCX with true lumen (green dots), false lumen with intramural hematoma (red dots) and guidewire in false lumen (yellow dots). 

Fig. 7: Culotte technique in LM, LAD and LCX. 

Fig. 8: Control angiography with dissection membrane in the first marginal branch of LCX.