Osami Kawarada

Stent-Assisted Below-the-Ankle Angioplasty for Limb Salvage:

Purpose: To report the clinical outcome of stent-assisted below-the-ankle angioplasty for limb salvage in the setting of critical limb ischemia (CLI). Methods: A retrospective single-center study was conducted of 40 critical ischemic limbs in 30 patients (mean age 67±8 years, range 46–94) undergoing below-the-ankle stent-assisted angioplasty between April 2006 and April 2009. Coronary bare metal stents were implanted in cases of failed balloon angioplasty due to significant recoil, flow-limiting dissection, abrupt closure, or repeat early reocclusion. Results: Technical success was 93% (37 limbs), with 3 failures to cross the occlusive lesions. Acute or subacute occlusion was evident in 9 (23%) limbs. The number of runoff vessels increased significantly (p<0.001) from 0.6±0.8 to 1.8±0.8. During a clinical follow-up of 19.3±11.4 months (range 1–48), the number of repeat interventions for limb salvage was 2.2±1.6 (range 1–9), and a total of 1.6±0.9 stents (range 1–3) were implanted in 8 dorsalis pedis arteries. Acute or subacute stent thrombosis after stenting was observed in 2 of these, and symptomatic in-stent restenosis was detected in 4, which were all treated by repeat intervention. At 6, 12, and 24 months, the freedom from repeat intervention was 39.6%, 39.6%, and 35.2%, respectively. Amputation-free survival was 80.0%, 69.7%, and 62.7%, and limb salvage was 94.7%, 91.4%, and 82.1% at the same time points. Patient survival rates were 77.4%, 71.0%, and 71.0%, respectively. During a mean follow-up of 13.4±12.7 months (range 1–31 months) in 7 of the 8 stented arteries, all examined stents were deformed: stent compression was evident in 5 and stent fracture in 5. However, 7 limbs undergoing dorsalis pedis artery stenting showed complete wound healing; 1 limb had a resistant wound in the heel. Conclusion: Stent-assisted below-the-ankle angioplasty produced a satisfactory clinical outcome but with the need for repeat intervention. Thus, further refinement in endovascular technology is mandatory to reduce the need for repeat interventions and to resolve stent deformity issues.

Assessment of Macro- and Microcirculation in Contemporary Critical Limb Ischemia

Objectives: A paucity of data exists regarding manifestations of macro‐ and microcirculation in contemporary critical limb ischemia (CLI). The aim of this study was (1) to evaluate the differences in foot circulation based on angiographic findings, (2) to clarify the relationship between macro‐ and microcirculation, and (3) to investigate the effects of postural changes on micro as well as macrocirculation between the supine position to the dependent position. Methods: A total of 40 critically ischemic limbs in 29 patients were included in this study. Noninvasive evaluation of macrocirculation, based on the ankle brachial index (ABI) and ankle pressure, and microcirculation, using skin perfusion pressure (SPP), was performed in both the supine and dependent positions. Results: There was no significant difference in macro‐ and microcirculations between any angiographical involvements. In the supine position, dorsal SPP correlated significantly with ABI (P = 0.021, r = 0.363) and ankle‐pressure (P = 0.001, r = 0.495), whereas plantar SPP failed to correlate with ABI (P = 0.198, r = 0.208) or ankle‐pressure (P = 0.185, r = 0.214). In the dependent position, however, SPP showed no significant correlation with ABI and ankle pressure. Postural change from the supine to dependent position yielded a significant increase in SPP (dorsal: 37.2 ± 16.2 to 77.9 ± 17.7 mm Hg, P < 0.001; plantar: 33.6 ± 17.3 to 75.7 ± 18.3 mm Hg, P < 0.001) as well as ABI and ankle‐pressure (ABI: 0.70 ± 0.35 to 0.78 ± 0.42, P = 0.003; ankle‐pressure; 108 ± 61 to 111 ± 60 mm Hg, P = 0.038). The effect of postural change on SPP showed no difference between patients with and without any clinical and angiographical complications. Conclusions: Of microcirculation assessed, only dorsal SPP correlated significantly with macrocirculation in the supine position. Furthermore, postural change from the supine to dependent position produced a dramatic improvement in microcirculation due to the effects of gravity.

Angioplasty of ulnar or radial arteries to treat critical hand ischemia: use of 3- and 4-French systems.

Objectives: The aim of this preliminary study is to report the results of catheter‐based treatment for isolated distal upper extremity artery disease with CHI. Background: Critical hand ischemia (CHI) is a rare but potentially devastating condition. Methods: The study consisted of five critically ischemic hands (Rutherford category 4: 2, Rutherford category 5: 3) in four patients undergoing catheter intervention for isolated distal upper extremity artery disease between November 2007 and April 2009. Results: Balloon angioplasty via an antegrade brachial approach was performed with a 3Fr or 4Fr sheath to achieve the principal endpoint of the establishment of one straight‐line flow to the palmar arch. All patients had end‐stage renal disease requiring chronic hemodialysis. The target vessels were the ulnar artery in four cases, the radial artery in one, and the palmar arch in two. Four cases had a stenotic lesion and one had chronic total occlusion. Technical success was achieved in all cases without complications, and skin perfusion pressure of the hand improved significantly from 39 ± 20 to 52 ± 16 (P = 0.019) on the palmar side and from 40 ± 18 to 60 ± 29 on the dorsal side (P = 0.046). Clinical success was achieved in all cases during a mean follow‐up period of 11 ± 8 (2–19) months. Conclusions: Percutaneous angioplasty using contemporary dedicated devices could be a potentially useful option for CHI patients with isolated distal upper extremity artery disease.

Awareness of anatomical variations for infrapopliteral intervention

With the tremendous advancement and accumulated expertise of endovascular techniques, infrapopliteal intervention is emerging as an alternative therapeutic option to distal bypass surgery for limb salvage in the setting of critical limb ischemia (CLI). However, though much attention has been given to infrapopliteal intervention, the importance of identifying preprocedural infrapopliteal variants remains underappreciated. Becoming more aware of these anatomical variants will translate to increased clinical effectiveness for the patient with infrapopliteal artery disease. Therefore, this review will highlight the fundamental aspects of infrapopliteal variant anatomy for the catheter‐based treatment of CLI patients with symptomatic infrapopliteal artery disease.© 2010 Wiley‐Liss, Inc.

Duplex criteria for in‐stent restenosis in the superficial femoral artery

Objectives: To elucidate the optimal cutoff and accuracy of duplex ultrasonography (DUS) parameters for in‐stent restenosis (ISR) after nitinol stenting in the superficial femoral artery (SFA). Background: Few data are available regarding the performance of DUS for binary ISR based on quantitative vessel analysis (QVA) in the era of SFA nitinol stenting. Methods: This retrospective study included 74 in‐stent stenoses of SFA who underwent DUS before follow‐up angiography. DUS parameters, such as peak systolic velocity (PSV) and the peak systolic velocity ratio (PSVR), were compared with percent diameter stenosis (%DS) from a QVA basis. Results: There was a statistically significant correlation (P < 0.001) between “%DS and PSV” and “%DS and PSVR,” and the correlation with %DS proved to be stronger in PSVR (R = 0.720) than in PSV (R = 0.672). The best performing parameter for ISR (50% or greater stenosis) was revealed PSVR, as the areas under the receiver operator characteristics curves using PSVR and PSV were 0.908 and 0.832, respectively. A PSVR cut off value of 2.85 yielded the best predictive value with sensitivity of 88%, specificity of 84%, and accuracy of 86%. The positive predictive value was 85% and the negative predictive value was 88%. Conclusions: A PSVR of 2.85 is the optimal threshold for ISR after nitinol stenting in the SFA. Further large prospective studies are required for the validation and establishment of uniform criteria for DUS parameters.

Native chronic total occlusion recanalization after lower limb bypass graft occlusion: a series of nine cases.

Objective: The aim of the study was to report the clinical utility of native chronic total occlusion (CTO) recanalization as an endovascular strategy in lower limb bypass graft occlusion. Background: There is no consensus on the best approach for threatened limbs in patients with graft occlusion. Methods: The subjects were nine consecutive patients with limb‐threatening ischemia after bypass graft occlusion. Native CTO recanalization was attempted endovascularly using conventional intraluminal and subintimal angioplasty techniques supported by stents. Results: The mean age of the bypass grafts was 6.7 ± 7.3 (range: 1–24) months and the mean number of previous lower limb bypass surgeries was 1.4 ± 0.5 (range: 1–2). Native CTO recanalization was performed in the iliofemoral (n = 2), iliac (n = 2), superficial femoral (n = 3), popliteal (n = 1), and popliteal‐tibial (n = 1) arteries. Technical success was achieved in 89% (8/9) of cases without complications or major adverse cardiovascular events. The ankle‐brachial index and skin perfusion pressure of the foot significantly increased after revascularization, with marked improvement of clinical symptoms (Rutherford class: 4.5 ± 1.1→0.9 ± 1.4, P < 0.001). Limb salvage was achieved in all successful recanalization cases during the mean follow‐up time of 25 ± 20 months (range: 9–60). Conclusions: In this preliminary study, endovascular recanalization of native CTO showed satisfactory outcomes in patients with bypass graft occlusion.

Variability in quantitative and qualitative analysis of intravascular ultrasound and frequency domain optical coherence tomography.

Frequency‐domain optical coherence tomography (FD‐OCT) is an intravascular imaging technique now available in the United States. However, the importance of level of training required for analysis using intravascular ultrasound (IVUS) and FD‐OCT is unclear. The aim of this study was to evaluate inter‐ and intra‐observer variability between expert and beginner analysts interpreting IVUS and FD‐OCT images.

Brain salvage for cardiac cerebral embolism following myocardial infarction

Acute ischemic stroke due to thromboembolism from the left ventricle is a serious complication following myocardial infarction (MI). Despite the attention given to acute stroke intervention, peri‐MI ischemic stroke is an underappreciated condition. Here, we describe a case of acute cardiac thromboembolic occlusion of the middle cerebral artery with preceding MI in which brain salvage was achieved by balloon angioplasty.

Impact of attenuated-signal plaque observed by intravascular ultrasound on vessel response after drug-eluting stent implantation

BACKGROUND AND AIMSnThe aim of this study was to investigate the impact of attenuated-signal plaque (ASP) observed by intravascular ultrasound (IVUS) on vessel response after drug-eluting stent implantation.nnnMETHODSnData were derived from the IVUS cohort of the J-DESsERT trial comparing paclitaxel- and sirolimus-eluting stents. Serial IVUS analysis (pre- and post-intervention, and 8-month follow-up) was performed in 136 non-AMI lesions. ASP was defined as hypoechoic plaque with ultrasound attenuation without calcification. Calcified plaque (CP) was defined as brightly echoreflective plaque with acoustic shadowing. ASP and CP scores were calculated by grading their measured angle as 0 to 4 for 0°, <90°, 90-180°, 180-270° and >270°, respectively. The entire stented segment was analyzed at 1-mm intervals.nnnRESULTSnAt pre-intervention, ASP was observed in 40.4% of lesions, and this group had greater % neointimal volume (%NIV) at follow-up than the no-ASP group (pxa0=xa00.011). ASP score at pre-intervention positively correlated with %NIV (pxa0=xa00.023). During the follow-up, ASP score significantly decreased (pxa0<xa00.001), and CP score significantly increased (pxa0<xa00.001), with a negative correlation between them (pxa0<xa00.001). A decrease in the ASP score was associated with less %NIV in PES (pxa0=xa00.031), but not in SES (pxa0=xa00.229).nnnCONCLUSIONSnThe greater extent of plaque with IVUS-signal attenuation at pre-intervention and its persistence during follow-up were associated with neointimal proliferation, possibly representing sustained inflammatory status, depending on the type of DES used.