Clinical expert consensus document on rotational atherectomy from the Japanese association of cardiovascular intervention and therapeutics

Evaluation of only heparin-based rota-flush solution against alternative rota-flush solution in patients with severe coronary artery calcification undergoing rotational atherectomy

Objective

There is limited evidence on feasibility and safety of only heparin rota-flush(OHRF)solution in rotational atherectomy (RA). We compared the safety and efficacy of OHRF solution with alternative rota-flush (ARF) solution in patients who underwent RA.

Methods

A total of 48 patients who underwent RA were enrolled in the study. In 25 patients OHRF solution and in 23 patients ARF solution was utilized. The study end points were procedural success rateandrota-related adverse cardiovascular event (RRAE) including slow flow, no reflow, bradycardia, and hemodynamic instability.

Results

Procedural success was achieved in all patients in both the OHRF and ARF groups. There was no statistically significant difference in RRAE between the two groups(32.0% vs. 34.7%, p = 0.83).

Conclusion

OHRF solution appears a more simplistic solution while performing rotablation as compared to ARF solution. Side effects such as hypotension and bradycardia can be circumvented with OHRF solution during rotablation.

Impact of the degree of wire bias in the vessel's healthy portion on coronary perivascular trauma in rotational atherectomy

BACKGROUND

In rotational atherectomy (RA), the risk of coronary perforation is considered to increase when the wire is in contact with the healthy portion of the vessel. However, the relationship between the extent of wire bias in the healthy portion of the vessel and the risk of coronary perivascular trauma (CPT) has not been reported.

METHODS

We examined 90 consecutive cases wherein intravascular ultrasound (IVUS) was performed before and after RA. The IVUS catheter in contact with the healthy region of the vessel was defined as the healthy portion wire bias (HWB), of which we measured the bias diameter, defined as the media-to-media length between the site where the IVUS catheter was in contact and the opposite side of the vessel. The bias ratio was defined as the ratio of the bias diameter to the short diameter at the region where the wire bias was the strongest. The relationship between the bias ratio and the CPT risk was evaluated.

RESULTS

CPT was significantly higher in the HWB group than in the non-HWB group (9% vs. 0%, P = 0.048). In the HWB group, the bias ratio was significantly greater in the CPT group than in the non-CPT group (1.31 ± 0.09 vs. 1.06 ± 0.06; P < 0.0001). The cutoff value of the bias ratio for CPT was 1.2, which was the maximum value of the sum of sensitivity 100% and specificity 97%.

CONCLUSIONS

Lesions without HWB had no CPT. CPT risk increased when the bias ratio exceeded 1.2.

Intravascular Imaging Guidance Reduce 1-Year MACE in Patients Undergoing Rotablator Atherectomy-Assisted Drug-Eluting Stent Implantation

Objectives: This study aimed to investigate the incidence of 1-year major adverse cardiac events (MACE) compared between intravascular imaging guidance and angiographic guidance in patients undergoing rotablator atherectomy (RA)-assisted percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation.

Methods: This retrospective analysis included 265 consecutive patients with heavy calcified lesion who underwent RA-assisted PCI with DES implantation at our institution during the January 2016-December 2018 study period. This study was approved by the Siriraj Institutional Review Board. Patients were divided into either the angiographic guidance PCI group or the imaging guidance PCI group, which was defined as intravascular ultrasound or optical coherence tomography. The primary endpoint was 1-year MACE.

Results: Two hundred and sixty-five patients were enrolled, including 188 patients in the intravascular imaging guidance group, and 77 patients in the angiographic guidance group. One-year MACE was significantly lower in the imaging guidance group compared to the angiographic guidance group (4.3 vs. 28.9%, respectively; odds ratio (OR): 9.06, 95% CI: 3.82–21.52; p < 0.001). The 1-year rates of all-cause death (OR: 8.19, 95% CI: 2.15–31.18; p = 0.002), myocardial infarction (MI) (OR: 6.13, 95% CI: 2.05–18.3; p = 0.001), and target vessel revascularization (TVR) (OR: 3.67, 95% CI: 1.13–11.96; p = 0.031) were also significantly lower in the imaging guidance group compared with the angiographic guidance group. The rate of stroke was non-significantly different between groups.

Conclusion: In patients with heavy calcified lesion undergoing RA-assisted DES implantation, the intravascular imaging guidance significantly reduced the incidence of 1-year MACE, all-cause death, MI, and TVR compared to the angiographic guidance.

Automatic detection of vessel structure by deep learning using intravascular ultrasound images of the coronary arteries

Intravascular ultrasound (IVUS) is a diagnostic modality used during percutaneous coronary intervention. However, specialist skills are required to interpret IVUS images. To address this issue, we developed a new artificial intelligence (AI) program that categorizes vessel components, including calcification and stents, seen in IVUS images of complex lesions. When developing our AI using U-Net, IVUS images were taken from patients with angina pectoris and were manually segmented into the following categories: lumen area, medial plus plaque area, calcification, and stent. To evaluate our AI's performance, we calculated the classification accuracy of vessel components in IVUS images of vessels with clinically significantly narrowed lumina (< 4 mm2) and those with severe calcification. Additionally, we assessed the correlation between lumen areas in manually-labeled ground truth images and those in AI-predicted images, the mean intersection over union (IoU) of a test set, and the recall score for detecting stent struts in each IVUS image in which a stent was present in the test set. Among 3738 labeled images, 323 were randomly selected for use as a test set. The remaining 3415 images were used for training. The classification accuracies for vessels with significantly narrowed lumina and those with severe calcification were 0.97 and 0.98, respectively. Additionally, there was a significant correlation in the lumen area between the ground truth images and the predicted images (ρ = 0.97, R2 = 0.97, p < 0.001). However, the mean IoU of the test set was 0.66 and the recall score for detecting stent struts was 0.64. Our AI program accurately classified vessels requiring treatment and vessel components, except for stents in IVUS images of complex lesions. AI may be a powerful tool for assisting in the interpretation of IVUS imaging and could promote the popularization of IVUS-guided percutaneous coronary intervention in a clinical setting.

Contemporary technologies to modify calcified plaque in coronary artery disease

With aging society, one of the more challenging obstacles in percutaneous coronary interventions are calcified coronary lesions. Calcified lesions may impede stent delivery, limit balloon and stent expansion, cause uneven drug distribution, and hinder wire advancement. Even in the setting of acceptable procedural success, vessel calcification is independently associated with increased target lesion revascularization rates at follow-up and lower survival rates. In order to effectively manage such lesions, dedicated technologies have been developed. Atherectomy aims at excising tissue and debulking plaques, as well as compressing and reshaping the atheroma, generally referred to as lesion preparation that enables further balloon and/or stent expansion in contemporary clinical practice. In the current review, we will discuss the available methods for atherectomy, including rotational, orbital, and excimer laser coronary atherectomy, as well as intravascular lithotripsy. In addition, we will review the role of imaging in calcified lesions.

Additional ablation effect of low-speed rotational atherectomy following high-speed rotational atherectomy on early calcified in-stent restenosis: A case report

Optical frequency domain imaging-guided additional low-speed rotational atherectomy following sufficient high-speed rotational atherectomy for early calcified in-stent restenosis might be a safe and useful option for achieving additional large lumen gains and stent expansion.

Comparison of the incidence of periprocedural myocardial infarction between percutaneous coronary intervention with versus without rotational atherectomy using propensity score-matching

Complications such as slow flow are frequently observed in percutaneous coronary intervention (PCI) with rotational atherectomy (RA). However, it remains unclear whether the high incidence of slow flow results in the high incidence of periprocedural myocardial infarction (PMI), reflecting real myocardial damage. The aim of this study was to compare the incidence of PMI between PCI with versus without RA using propensity score-matching. We included 1350 elective PCI cases, which were divided into the RA group (n = 203) and the non-RA group (n = 1147). After propensity score matching, the matched RA group (n = 190) and the matched non-RA group (n = 190) were generated. The primary interest was to compare the incidence of PMI between the matched RA and non-RA groups. Before propensity score matching, the incidence of slow flow and PMI was greater in the RA group than in the non-RA group. After matching, the incidence of slow flow was still greater in the matched RA group than in the matched non-RA group (16.8% vs. 9.5%, p = 0.048). However, the incidence of PMI was similar between the matched RA and matched non-RA group (7.4% vs. 5.3%, p = 0.528, standardized difference: 0.086). In conclusion, although use of RA was associated with greater risk of slow flow, use of RA was not associated with PMI after a propensity score-matched analysis. The fact that RA did not increase the risk of myocardial damage in complex lesions would have an impact on revascularization strategy for severely calcified coronary lesions.

Modifiable and unmodifiable factors associated with slow flow following rotational atherectomy

Background

Although several groups reported the risk factors for slow flow during rotational atherectomy (RA), they did not clearly distinguish modifiable factors, such as burr-to-artery ratio from unmodifiable ones, such as lesion length. The aim of this retrospective study was to investigate the modifiable and unmodifiable factors that were associated with slow flow.

Methods

We included 513 lesions treated with RA, which were classified into a slow flow group (n = 97) and a non-slow flow group (n = 416) according to the presence or absence of slow flow just after RA. The multivariate logistic regression analysis was performed to find factors associated with slow flow.

Results

Slow flow was inversely associated with reference diameter [Odds ratio (OR) 0.351, 95% confidence interval (CI) 0.205–0.600, p<0.001], primary RA strategy (OR 0.224, 95% CI 0.097–0.513, p<0.001), short single run (≤15 seconds) (OR 0.458, 95% CI 0.271–0.776, p = 0.004), and systolic blood pressure (BP) ≥ 140 mmHg (OR 0.501, 95% CI 0.297–0.843, p = 0.009). Lesion length (every 5 mm increase: OR 1.193, 95% CI 1.093–1.301, p<0.001), angulation (OR 2.054, 95% CI 1.171–3.601, p = 0.012), halfway RA (OR 2.027, 95% CI 1.130–3.635, p = 0.018), initial burr-to-artery ratio (OR 1.451, 95% CI 1.212–1.737, p<0.001), and use of beta blockers (OR 1.894, 95% CI 1.004–3.573, p = 0.049) were significantly associated with slow flow.

Conclusions

Slow flow was positively associated with several unmodifiable factors including lesion length and angulation, and inversely associated with reference diameter. In addition, slow flow was positively associated with several modifiable factors including initial burr-to-artery ratio and use of beta blockers, and inversely associated with primary RA strategy, short single run, and systolic blood pressure just before RA. Application of this information could help to improve RA procedures.