Subclavian Artery Stenosis: Prevalence, Risk Factors, and Association With Cardiovascular Diseases

When a subclavian artery is equivalent to STEMI of left main coronary artery: a case report

An 81-year-old man with known ischemic heart disease and coronary artery bypass graft (CABG) was admitted with cardiogenic shock and ST segment elevation myocardial infarction (STEMI) of the anterior and lateral wall. Coronary angiography showed a total occlusion of left main coronary artery and acute thrombotic proximal segmental occlusion of the left subclavian artery before the origin of left internal mammary artery (LIMA). Successful percutaneous intervention proximal to the LIMA origin led to immediate restoration of antegrade flow in the left internal mammary artery (LIMA) to the left coronary circulation, stabilizing hemodynamics, and relieving symptoms.

Hospitalized upper extremity artery disease patients: treatment and long-term outcomes

BACKGROUND AND AIMS

Current knowledge about upper extremity artery disease (UEAD) is scarce. This study aimed to evaluate the prevalence, treatment patterns, and short- and long-term outcomes of patients suffering from UEAD.

METHODS

Retrospective health claims data of patients who were hospitalized with a primary diagnosis of UEAD between 2010 and 2017 were analysed. The data were obtained from 11 legally independent statutory health insurance funds of the 'AOK-Die Gesundheitskasse'. Risk factors, comorbidities, pharmacotherapy, revascularization procedure, and outcome were evaluated with a particular focus on sex-related disparities (median follow-up time: 5.5 years).

RESULTS

Among 2437 UEAD patients (43% female, median age of 67 years), 80% were solely atherosclerotic (UEADa), while 20% had concomitant inflammatory/connective tissue diseases (UEADc/i). Cardiovascular risk factors and comorbidities were highly prevalent in both sexes. Coronary, cerebrovascular, and lower extremity artery diseases and organ failure such as chronic kidney and heart failure were more frequent in men compared with women. At index stay, women had higher rate of revascularization than men (37% vs. 27%). The 5 year mortality among the entire population was almost 50%, even higher in men (UEADa: 51% vs. 36% P < .001; UEADc/i: 44% vs. 36%, P < .05). Furthermore, men had higher rates of upper limb amputation compared with women despite equal secondary preventive pharmacotherapy (UEADa: 26% vs. 11%, P < .001; UEADc/i: 30% vs. 18%, P < .01).

CONCLUSIONS

Upper extremity artery disease patients, irrespective of the underlying disease type, face a poor prognosis with elevated proportion of amputation and mortality. Male sex was linked to increased risk of future cardiovascular and limb events including death. Further investigation is warranted to understand the underlying causes of the sex-related disparities and identify treatment improvements.

Symptomatic Upper Extremity Peripheral Artery Disease is Associated With Poor Outcomes and a Broad Spectrum of Etiologies

The symptomatic upper extremity peripheral artery disease (sUE-PAD) is poorly studied compared with the lower extremity peripheral artery disease (LE-PAD). We aimed to describe sUE-PAD etiologies and outcomes at 2 years. From an observational survey conducted in two French tertiary hospitals, demographic characteristics, etiology, treatment, and outcomes during follow-up were collected on patients with ICD-10 I74.2 code (arterial thrombosis of the upper limbs). We identified 181 patients (53% male, 55 ± 17 years) with hypothenar hammer syndrome (13.8%), cardioembolism (13.3%), atheroma (12.7%), or connective tissue disease (10.5%). No etiology could be found for 16.0% of them. The amputation rate was 13.3%, and lasting symptoms remained at 21.3%. During follow-up, atrial fibrillation occurred in 1 patient and cancer in 4. At 2 years, 59 patients were lost to follow-up, 110 patients were alive, and 12 patients had died. Age and cancer were associated with death. sUE-PAD is not benign, with 20% impaired upper extremity outcome and 10% overall mortality at 2 years. Less frequent than LE-PAD, sUE-PAD presents different characteristics: more women, younger age, and a broad spectrum of etiologies. sUE-PAD requires thorough etiological assessment and is considered to be associated with a severe overall prognosis.

Long-term outcomes of endovascular therapy for right subclavian artery occlusive lesions: A multi-center experience

ObjectiveTo review our multi-institutional experience with endovascular therapy for right subclavian artery occlusive disease and to evaluate the long-term outcomes.MethodsWe retrospectively evaluated all patients with right subclavian artery stenosis and occlusive disease who underwent endovascular therapy between March 2014 and September 2022 at two institutions. Patient baseline demographics, lesion characteristics, treatment strategies, and in-hospital and follow-up outcomes were prospectively collected and retrospectively analyzed.ResultsBetween March 2014 and September 2022, 73 patients underwent endovascular treatment at the two institutions. The dominant cause of lesions in this cohort was atherosclerosis. Three different types of lesions were summarized, and the corresponding endovascular strategies were performed. 66 patients (90.4%) underwent successful endovascular treatment, and 62 patients (84.9%) underwent balloon-expandable stent deployment. The mean perioperative in-hospital stay was 4.0 days (range, 3-6 days). Two patients died due to myocardial infarction, and one died of cerebral hemorrhage resulting from a traffic accident within 30 days of the intervention. The median follow-up time was 31.6 months (range, 12-96 months). No complications, including death, stroke, stent fractures, or migration, were noted in any patient during the follow-up period. The overall complication rate was 7/73 (9.6%), and 5/7 (6.9%) of the complications required reintervention.ConclusionsEndovascular treatment of right subclavian artery lesions is safe, effective, and technically achievable. The reasonable use of balloon-expandable stents can achieve satisfactory outcomes with accurate orientation and promising patency.

Frequency of subclavian steal syndrome in a sample of non-Western population

BACKGROUND

Subclavian steal syndrome (SSS) is not rarely found during ultrasound examinations. Previous reports demonstrated a relation between ethnic factors and SSS. Data regarding SSS in non-Western population are still lacking. We aimed to investigate the frequency of SSS in a sample of Egyptian population.

METHODS

In a single-center observational study, we conducted a retrospective analysis of successive patients with competent ultrasound examinations of the brain supplying vessels. The patients presented to our neurovascular laboratory in the context of routine clinical practice.

RESULTS

We enrolled 514 patients in our study. SSS was detected in 9 patients (1.8 %) with a median (IQR) age of 58 (56-63) years. One patient with second-degree SSS received a subclavian stent. Among patients with SSS, 4 patients (44.4 %) had carotid atherosclerosis, 4 patients (44.4 %) had ischemic vascular events in the posterior circulation, and two (22.2 %) had hemodynamically significant carotid stenosis ≥50 %. Using a ROC curve, an interarm SBP (systolic blood pressure) difference of ≥10 mmHg had a sensitivity of 77.8 % and specificity of 66 %, whereas a difference of ≥20 mmHg was associated with a sensitivity of 55.6 % and specificity of 92.4 % for SSS (AUC 0.79, 95 % CI 0.6-0.97, p = 0.004).

CONCLUSIONS

SSS is not rare among Egyptian population and should be in mind during ultrasound examination, especially for patient with ischemic events in the posterior circulation and those with significant interarm SBP difference.

Correlation between carotid and/or subclavian atherosclerotic plaque and coronary atherosclerotic disease

BACKGROUND AND AIM

The present study aimed to analyze the correlation between carotid atherosclerotic plaque (CAP) and/or subclavian atherosclerotic plaque (SAP) and coronary atherosclerosis disease (CASD).

METHODS

A total of 1343 patients hospitalized for chest pain or tightness due to coronary atherosclerotic disease and underwent initial coronary angiography (CAG) were evaluated by color Doppler flow imaging (CDFI) for CAP and SAP. The patients were divided into four groups: non-CAP & non-SAP, only-SAP, only-CAP, or CAP & SAP. Finally, 1,242 patients were included in this study.

RESULTS

The incidence of CASD and main coronary artery disease in the CAP & SAP group was higher than that in the CAP-only group. Moreover, the detection rate of three-vessel disease (3-VD) in the CAP & SAP group was significantly higher than that in the CAP group (p < 0.05). The incidence of main coronary artery branch lesions in patients with CAP & SAP was approximately 1.5 times higher than in those with only CAP. Male gender, hypertension, and diabetes were independent risk factors for main coronary artery branch lesions. If the patient had CAP & SAP lesions and more than three cardiovascular disease risk factors, coronary artery main artery disease incidence was about 81.7% CONCLUSION: Based on the CDFI screening and combined with cardiovascular disease risk factors, the combined evaluation of CAP and SAP showed higher CASD prediction values than the CAP group alone. Early detection of coronary atherosclerotic stenosis and timely clinical intervention is expected to reduce the incidence of ischemic heart disease events caused by coronary atherosclerotic stenosis.

Case report: a case of masked subclavian artery stenosis in a haemodialysis patient

Background

Subclavian artery stenosis is generally screened by a left-right brachial systolic blood pressure difference. However, subclavian artery stenoses are often underdiagnosed due to marginally identified symptoms. In dialysis patients, a relative or absolute contradiction of measuring blood pressure in shunt brachial artery may further limit the disease screening.

Case summary

A 77-year-old female requiring dialysis presented with a suspected acute coronary syndrome complicated by cardiogenic shock. Five months before presentation, the patient was increasingly given inotropic drugs and had often chest discomfort during dialysis. An emergency coronary angiogram of the right coronary artery revealed 99% stenosis with hypoplasia. During catheterization, angiography of the aortic arch showed subtotal occlusion of the left subclavian artery. After revascularization, patients did not suffer from low blood pressure during haemodialysis.

Discussion

Dialysis patients may have high perceived risk of subclavian artery stenosis. However, limitation of measuring blood pressure in shunt artery may enhance its underdiagnosis. Our case highlights the importance of screening for subclavian artery stenosis in patients undergoing dialysis.

Target Heart Rate Formulas for Exercise Stress Testing: What Is the Evidence?

Exercise stress testing (EST) is commonly used to evaluate chest pain, with some labs using 85% of age-predicted maximum heart rate (APMHR) as an endpoint for EST. The APMHR is often calculated using the formula 220-age. However, the accuracy of this formula and 85% APMHR as an endpoint may be questioned. Moreover, failing to reach 85% APMHR (known as chronotropic insufficiency) may also indicate poor cardiovascular prognosis, but measurements, such as percentage heart rate reserve (%HRR), maximum rate pressure product (MRPP), and the maximum metabolic equivalent of tasks (METs) reached during EST may provide better prediction of cardiovascular outcomes than not reaching 85% of APMHR. There is a need to incorporate comprehensive measurements to improve the diagnostic and prognostic capabilities of EST.

Effects of percutaneous endovascular angioplasty for severe stenosis or occlusion of subclavian artery

To investigate the effect and safety of percutaneous endovascular angioplasty (PEA) with optional stenting for the treatment of severe stenosis or occlusion of subclavian artery, patients with severe stenosis ≥ 70% or occlusion of subclavian artery treated with PEA were retrospectively enrolled. The clinical data were analyzed. A total of 222 patients were retrospectively enrolled, including 151 males (68.0%) and 71 females (32.0%) aged 48-86 (mean 63.9 ± 9.0) years. Forty-seven (21.2%) patients had comorbidities. Subclavian artery stenosis ≥ 70% was present in 201 (90.5%) patients and complete subclavian occlusion in 21 (9.5%) cases. Angioplasty was successfully performed in all (100%) patients. Balloon-expandable stents were used in 190 (85.6%) cases, and self-expandable stents in 20 (9.0%) cases. Only 12 (5.4%) cases were treated with balloon dilation only. Among 210 patients treated with stent angioplasty, 71 (33.8% or 71/210) cases underwent balloon pre-dilation, 139 (66.2% or 139/210) had direct deployment of balloon-expandable stents, and 2 (1.0% or 2/210) experienced balloon post-dilation. Distal embolization protection devices were used in 5 (2.3% or 5/222) cases. Periprocedural complications occurred in 3 (1.4%) patients, including aortic dissection in 2 (0.9%) cases and right middle cerebral artery embolism in 1 (0.5%). No hemorrhage occurred. Among 182 (82.0%) patients with 6-month follow-up, restenosis > 70% occurred in 1 (0.5%) patient, and among 68 (30.6%) patients with 12-month follow-up, restenosis > 70% took place in 11 (16.2%) patients. Percutaneous endovascular angioplasty can be safely and efficiently performed for the treatment of severe stenosis ≥ 70% or occlusion of subclavian artery.

Atypical presentation of subclavian steal syndrome with left sided sensorineural deafness

We present a rare manifestation of a common pathology: left sided sensorineural hearing loss secondary to subclavian steal syndrome after thoracic endovascular aortic repair for complicated acute aortic dissection. We describe the vascular physiology that can result in unilateral hearing loss and provide a brief review of subclavian steal syndrome. This case report highlights the importance of avid clinical recognition of an atypical presentation of a common vascular disease.

Cardiovascular Prognosis in Patients with Peripheral Artery Disease and Approach to Therapy

Peripheral artery disease (PAD), the pathophysiologic narrowing of the arterial blood vessels of the lower limbs due to atherosclerosis, is estimated to affect more than 200 million people worldwide and its prevalence ranges from 0.9 to 31.3% in people aged ≥50 years. It is an established marker of systemic obstructive atherosclerosis, which depicts patients at higher risk of myocardial infarction and stroke, due to the involvement of coronary and cerebral arteries in the atherosclerotic process. Therefore, identifying PAD, particularly in patients with coronary artery disease, is important to assess the cardiovascular risk score and implement specific therapies and prevention strategies. Since PAD emerged as an important clinical cardiovascular predictor, even more than other typical cardiovascular risk factors, an aggressive strategy to identify and treat PAD patients should be pursued by general practitioners, cardiologists, and vascular surgeons; similarly, preventive strategies should be implemented to improve prognosis and outcomes, particularly in patients suffering from both coronary artery disease and PAD. In this review, we describe the pathophysiology, including limb vasoconstriction after coronary angioplasty, the diagnosis of PAD, prognosis according to cardiovascular events, coronary artery disease, and heart failure. Furthermore, a large section of this review is on management, which spans from risk factors' modification to antithrombotic therapy, and revascularization is provided. Finally, considerations about newer therapeutic options for the "desert foot" are discussed, including gene therapy.

Association between interleg systolic blood pressure difference and apparent peripheral neuropathy in US adults with diabetes: a cross-sectional study

BACKGROUND

Interleg systolic blood pressure difference (ILSBPD) is associated with peripheral artery disease, but the relationship between ILSBPD and apparent peripheral neuropathy in diabetic patients remains unclear. We explored the relationship between ILSBPD and apparent peripheral neuropathy and examined the possible effect modifiers in US adults with diabetes.

METHODS

One thousand and fifty-one diabetic participants were included in the study with complete data on systolic blood pressure of the lower extremities and Semmes-Weinstein 10-g monofilament testing from the 1999-2004 National Health and Nutritional Examination Surveys. Systolic blood pressure in the lower extremities was measured using an oscillometric blood pressure device with the patient in the supine position. Apparent peripheral neuropathy was defined as the presence of monofilament insensitivity.

RESULTS

Every 5-mmHg increment in ILSBPD is associated with an about 14% increased risk of apparent peripheral neuropathy in crude model, but after adjustment for covariates, the correlation became nonsignificant (P = 0.160). When participants were divided into groups based on ILSBPD cutoffs of 5, 10 and 15 mmHg in different analyses, there was a significantly increased risk of apparent peripheral neuropathy in the ILSBPD ≥ 15 mmHg group (OR 1.79, 95% CI 1.11-2.91, P = 0.018), even after adjusting for confounders. In subgroup analysis, no interaction effect was found (all P for interaction > 0.05).

CONCLUSIONS

In US adults with diabetes, an increase in the ILSBPD (≥ 15 mmHg) was associated with a higher risk of apparent peripheral neuropathy.

Frequency of subclavian artery stenosis in patients with mammarian artery coronary bypass and suspected coronary artery disease progression

We retrospectively analyzed patient records of all patients with a history of internal mammarian artery (IMA) coronary bypass undergoing coronary angiography at two cardiovascular centers between January 1st 1999 and December 31st 2019. A total of 11,929 coronary angiographies with or without percutaneous coronary intervention were carried out in 3921 patients. Our analysis revealed 82 (2%) patients with documented subclavian artery stenosis. Of these, 8 (10%) patients were classified as having mild, 18 (22%) moderate, and 56 (68%) severe subclavian artery stenosis. In 7 (9%) patients with subclavian artery stenosis, angiography revealed occlusion of the IMA graft. 26 (32%) patients with severe subclavian artery stenosis underwent endovascular or surgical revasculararization of the subclavian artery. In this retrospective multicenter study, subclavian artery stenosis was a relevant finding in patients with an internal mammarian artery coronary bypass graft undergoing coronary angiography. The development of dedicated algorithms for screening and ischemia evaluation in affected individuals may improve treatment of this potentially underdiagnosed and undertreated condition.

Endovascular Treatment for Subclavian Artery Stenosis and Occlusion: A Single-Center Retrospective Study

BACKGROUND

Subclavian artery stenosis and occlusion are common arterial diseases in the upper extremities, with atherosclerosis being the main cause. Endovascular treatment has emerged as a promising alternative to open surgical repair, but data are limited. This study aimed to evaluate the safety and effectiveness of endovascular procedures in the treatment of subclavian artery lesions at a tertiary vascular center in Vietnam.

METHODS

A retrospective analysis was conducted on patients who underwent endovascular treatment for symptomatic subclavian artery stenosis or occlusion between October 2013 and April 2022. Clinical characteristics, procedural details, short- and long-term outcomes, and patency rates were assessed.

RESULTS

Twenty-five patients were included in the study, with a mean age of 56.8 years. The majority of patients had risk factors for atherosclerosis, and all presented with symptoms related to subclavian artery disease. The endovascular procedures were successful in 96% of cases, with a low complication rate of 8%. During a median follow-up of 43 months, the overall patency rate was 92% at three years.

CONCLUSION

Endovascular treatment of subclavian artery stenosis and occlusion is a safe and effective option, with excellent long-term patency rates. These findings support the use of percutaneous revascularization as the first-line therapy, particularly in experienced centers. Further studies with larger sample sizes and longer follow-up periods are needed to confirm these results.

Clinic furniture arrangements leading to patient self-reported blood pressure discrepancy: a rare case of total occlusion of left subclavian artery

Subclavian artery occlusion is an uncommon condition affecting approximately 2% of the general population. Only 8.7% of patients with total occlusion of subclavian artery are asymptomatic. It has the potential to cause significant morbidity as it could contribute to the ischemic complications affecting the upper extremities, brain, and heart. We present a case of asymptomatic total occlusion of left subclavian artery which was found following investigations for discrepancy in blood pressure readings from the patient’s right and left arm. The difference was noted due to the clinic’s furniture arrangement. The patient was treated with stent insertion via percutaneous transluminal angioplasty. After three years of follow ups, she remains asymptomatic and free of cardiovascular-related complications.

Correlation between Coronary Artery Disease with Other Arterial Systems: Similar, Albeit Separate, Underlying Pathophysiologic Mechanisms

Atherosclerosis is a multifactorial systemic disease that affects the entire arterial tree, although some areas are more prone to lipid deposits than others. Moreover, the histopathological composition of the plaques differs, and the clinical manifestations are also different, depending on the location and structure of the atherosclerotic plaque. Some arterial systems are correlated with each other more than in that they simply share a common atherosclerotic risk. The aim of this perspective review is to discuss this heterogeneity of atherosclerotic impairment in different arterial districts and to investigate the current evidence that resulted from studies of the topographical interrelations of atherosclerosis.

Variant of subclavian steal syndrome: unusual anatomical relationship between left subclavian artery and left vertebral artery

A woman in her 70s presented to her general practitioner (GP) with a 3-month history of left upper arm pain and weakness. A significant difference in bilateral blood pressures was noted and a further history elicited coolness in her left arm without functional compromise. A CT angiography revealed variant subclavian steal syndrome with a subclavian arterial stenosis, which was proximal to both the internal mammary and thyrocervical trunk and her left vertebral artery originating from the aortic arch. She was referred to a vascular surgeon but declined surgical intervention. Her symptoms remain stable with 6-month follow-up from her GP. This case highlights the importance of considering vascular aetiologies in upper limb pain and weakness. Our case reviews the differential diagnoses of upper limb pain and weakness, consequently leading to the discussion of an interesting variant of subclavian stenosis.

Inter-arm systolic blood pressure difference: non-persistence and association with incident cardiovascular disease in the Multi-ethnic Study of Atherosclerosis

We investigated inter-arm systolic blood pressure (sIAD) difference, reproducibility, and incident cardiovascular disease (CVD). We hypothesized that higher sIAD values have low prevalence and nonpersistence over years, but that CVD risk is higher starting from the time of first high absolute sIAD. In Multi-Ethnic Study of Atherosclerosis participants (n = 6725, 53% female, 45-84 years old), Doppler systolic blood pressure (SBP) measurements were made in both arms (10-minute interval) thrice over 9.5 years. Proportional hazards for CVD (coronary heart disease, heart failure, stroke, peripheral arterial disease (PAD)) over 16.4 years were tested according to time-varying absolute inter-arm difference with covariates: (1) age, gender, race, and clinic; (2) model 1 plus height, heart rate, BP, antihypertensives, BMI, smoking status, lipids, lipid lowering medication, and diabetes. High sIAD was not persistent across exams. Maximum absolute sIAD ≥ 15 mmHg was found at least once in 815 persons. Maximum absolute sIAD had a graded relationship with incident stroke or PAD: 6.2% events; model 2 hazard ratio per 10 mmHg 1.34 (95% CI, 1.15-1.56) and this risk was approximately doubled for maximum absolute sIAD ≥ 15 mmHg vs 0-4 mmHg. Total CVD risk (18.4% events) was increased only for maximum absolute sIAD ≥25 mmHg. Associations with incident CVD did not differ for higher SBP in left vs right arm. A higher maximum absolute sIAD at any exam was associated with greater risk for stroke and PAD especially for values ≥ 15 mmHg, and ≥25 mmHg for other CVD. Measuring SBP between arms may help identify individuals at risk for CVD.

[Treatment of atherosclerotic lesion of the first segment of subclavian artery]

Severe subclavian artery lesion is an important medical and social problem worsening the quality of life and leading to dire consequences. Vertebrobasilar insufficiency is the main syndrome of lesion of the first segment of subclavian artery. About 20% of all ischemic strokes occur in vertebrobasilar basin. At present, surgical treatment of asymptomatic patients with severe lesion of the 1st segment of subclavian artery is still debatable. Open surgery is optimal for occlusion of this vascular segment. Carotid-subclavian transposition is a preferable option with favorable in-hospital and long-term results. However, carotid-subclavian bypass is an equivalent alternative in case of difficult transposition following anatomical and topographic features of vascular architectonics. Endovascular treatment is preferable for isolated subclavian artery stenosis and should certainly include stenting.

Dysregulated Genes, MicroRNAs, Biological Pathways, and Gastrocnemius Muscle Fiber Types Associated With Progression of Peripheral Artery Disease: A Preliminary Analysis

Background Peripheral artery disease (PAD) is associated with gastrocnemius muscle abnormalities. However, the biological pathways associated with gastrocnemius muscle dysfunction and their associations with progression of PAD are largely unknown. This study characterized differential gene and microRNA (miRNA) expression in gastrocnemius biopsies from people without PAD compared with those with PAD. Participants with PAD included those with and without PAD progression. Methods and Results mRNA and miRNA sequencing were performed to identify differentially expressed genes, differentially expressed miRNAs, mRNA-miRNA interactions, and associated biological pathways for 3 sets of comparisons: (1) PAD progression (n=7) versus non-PAD (n=7); (2) PAD no progression (n=6) versus non-PAD; and (3) PAD progression versus PAD no progression. Immunohistochemistry was performed to determine gastrocnemius muscle fiber types and muscle fiber size. Differentially expressed genes and differentially expressed miRNAs were more abundant in the comparison of PAD progression versus non-PAD compared with PAD with versus without progression. Among the top significant cellular pathways in subjects with PAD progression were muscle contraction or development, transforming growth factor-beta, growth/differentiation factor, and activin signaling, inflammation, cellular senescence, and notch signaling. Subjects with PAD progression had increased frequency of smaller Type 2a gastrocnemius muscle fibers in exploratory analyses. Conclusions Humans with PAD progression exhibited greater differences in the number of gene and miRNA expression, biological pathways, and Type 2a muscle fiber size compared with those without PAD. Fewer differences were observed between people with PAD without progression and control patients without PAD. Further study is needed to confirm whether the identified transcripts may serve as potential biomarkers for diagnosis and progression of PAD.

Usefulness of stent placement for innominate artery stenosis via the right brachial artery under protection by balloon guide catheter: a technical case report

A method of cerebral protection during endovascular treatment for innominate artery stenosis (IAS) has not been established. Herein, we report a case of symptomatic IAS in a 76-year-old woman. A balloon guide catheter (BGC) was inserted through the right brachial artery (BA) and guided distally to the stenosis. The BGC balloon was inflated, and stenting was performed with balloon protection of both the anterior and posterior cerebral circulation, without any complications. Stenting of the IAS with the BGC using the BA approach is useful, as it is a simple technique that can prevent distal embolization.

Computed Tomography Angiography in the Diagnosis of Subclavian-Vertebral Artery Steal

Purpose

Computed tomography angiography (CTA) is commonly used in the diagnosis and evaluation of subclavian steal (SS). However, the abnormal manifestations of vertebral artery (VA) in SS on CTA are vastly under-recognized and prone to misdiagnosis. We reported for the first time the abnormal CTA manifestations of VA in SS, and evaluated the value and pitfalls of CTA in the diagnosis of SS, aiming to avoid misdiagnosis and facilitate correct diagnosis of SS using CTA.

Patients and Methods

This study retrospectively included 19 patients diagnosed with SS using carotid duplex sonography (CDS) and digital subtraction angiography (DSA) between 2018 and 2022 at a tertiary neurology clinic in Chongqing, China. Their CDS, DSA and CTA results were collected and analyzed. The diagnostic consistency between CTA and DSA in grading subclavian artery stenosis was evaluated, and the CTA manifestations of VA were summarized.

Results

All patients presented subclavian steno-occlusion on the affected side, without steno-occlusion of the contralateral subclavian artery or bilateral VA on DSA. A high concordance was observed between CTA and DSA in grading subclavian artery stenosis (Kappa = 0.825, P = 0.000). However, only 26.3% of patients presented normal VA on CTA, whereas 73.7% of patients presented shallow VA ipsilateral to subclavian steno-occlusion. A 28.6% of patients with shallow VA were misdiagnosed as having vertebral arteriopathy. The presence of shallow VA had no significant correlation with age, gender, severity of subclavian artery stenosis, diameter of VA or model of CT scanner (all P>0.05). Although not statistically significant, the incidence of shallow VA increased with higher SS grade.

Conclusion

Carotid CTA is highly accurate for diagnosing subclavian steno-occlusion, whereas shallow VA is the pitfall of CTA in diagnosing SS. It is important to improve the recognition of shallow VA to avoid misdiagnosis.

Subclavian Steal Phenomenon Associated With Vascular Ring in an Infant Who Had a Prenatally Diagnosed Right Aortic Arch With an Atretic Aberrant Left Subclavian Artery

Vascular ring is a rare congenital anomaly in which the abnormal origin of the aorta or its branches and pulmonary arteries leads to encircling and compression of the trachea and esophagus. A right aortic arch (RAA) with an aberrant left subclavian artery is one of the most common forms of vascular ring. Here, we report a case of a prenatally diagnosed vascular ring resulting from an RAA with an aberrant left subclavian artery. When the infant was 7 months of age, the development of noisy breathing prompted further evaluation with cardiac magnetic resonance imaging that showed an atretic left subclavian artery associated with collateral retrograde flow from the left vertebral artery to the distal portion of the subclavian artery. Our findings indicate that an untreated RAA with an aberrant left subclavian artery may be associated with an increased risk of developing subclavian artery steal syndrome.

Evaluation of the role of combining inter-arm systolic pressure difference and derivatives of pulse volume recording in detecting subclavian artery stenosis

Background

Subclavian artery stenosis (SAS) is a peripheral arterial disease of asymptomatic appearance and disastrous consequences. The traditional screening method remains unsatisfactory.

Objective

The study aimed to assess the diagnostic performances of inter-arm systolic pressure difference (IASBPD), derivatives of pulse volume recording (PVR), and their combination in detecting subclavian artery stenosis.

Materials and methods

The present study was a retrospective analysis of clinical data from inpatients suspected of supra-arch artery stenosis in Fuwai hospital during 1 year, who underwent selective arterial angiographies. We obtained simultaneous blood pressure measurements on four limbs and pulse waves for calculating IASBPD and PVR derivatives prior to the angiographies. We utilized the receiver operating characteristic curve (ROC) to calculate the optimal cut-off value of IASBPD, upstroke time (UT), and upstroke time per cardiac cycle (UTCC) for detecting SAS. Moreover, we compared the sensitivity and specificity of IASBPD, UT, UTCC, and their combinations for diagnosing SAS (Clinical trial number: NCT03521739).

Results

We consecutively enrolled 320 eligible patients. Based on SAS’s definition of stenosis above 50%, the area under the curve of IASBPD, UT, and UTCC were 0.84, 0.76, and 0.80 (P < 0.001). And their corresponding cut-off points were 9 mmHg, 202 milliseconds, and 23.2%. The sensitivity and specificity of IASBPD ≥ 9 mmHg were 57.0 and 94.1%. UT ≥ 202 ms and UTCC ≥ 23.2% yielded similar sensitivity (72.6 vs. 72.6%, P > 0.05), but UTCC had higher specificity (81.1 vs. 72.4%, P < 0.05). The sensitivity of the combination of IASBPD and UT (85.2%) or UTCC (78.5%) was significantly higher than IASBPD alone (57%, P < 0.05). The specificity of either combination decreased to 67.6 and 76.8% (P < 0.05).

Conclusions

This present study showed that the combinations of IASBPD and PVR-derived parameters promoted diagnostic sensitivity and preserved adequate specificity than those alone for detecting SAS.

Coronary subclavian steal syndrome causing acute coronary syndrome: a case report

Background

Myocardial infarction on non-occluded coronary artery represents a very specific subset of acute coronary syndrome (ACS). Coronary subclavian steal syndrome (CSSS) is defined by a left subclavian artery stenosis in case of (i) left internal mammary artery (LIMA) used to bypass left anterior descending artery (LAD) and (ii) &gt;75% stenosis of the left subclavian artery prior to the origin of the LIMA to LAD graft. Here we report the case of a CSSS causing ACS.

Case summary

A 71-year-old man with history of LIMA to LAD coronary artery bypass surgery was admitted to the nephrology intensive care unit for acute kidney injury requiring dialysis. Due to rapid deterioration, altered left ventricular ejection fraction and elevated c-troponin levels, an urgent coronary angiography was performed. It revealed a subtotal occlusion of the left subclavian artery prior to the origin of the LIMA to LAD graft. This was responsible for a severely altered coronary flow in the LIMA and LAD. Revascularization of the proximal left subclavian artery with a stent was performed, enabling instant recovery of distal coronary flows.

Discussion

ACS due to CSSS in this report highlights the complexity of the cardio–renal interaction. Patients with coronary artery bypass graft and chronic kidney disease commonly exhibit a higher risk for severe progression of atherosclerosis at multiple sites. CSSS treatments include secondary prevention measures and revascularization (if indicated) such as an endovascular approach.

Subclavian atherectomy and angioplasty for coronary subclavian steal syndrome post CABG

Coronary subclavian steal syndrome is an uncommon complication occurring in patients with coronary artery bypass graft (CABG). We describe a case of a 69-year-old male with a remote history of CABG who presented with exertional left arm pain and angina. Computed Tomographic Angiography of the chest demonstrated a severe left proximal subclavian artery stenosis. The case demonstrates successful application of subclavian atherectomy with use of embolic protective device, alleviating the need of stent, for treatment of Coronary subclavian steal syndrome in patient with remote history of CABG.

Transcarotid artery revascularization in reverse for innominate artery stenosis

Stenotic lesions of the supra-aortic vessels have been reported in 2-6% of patients presenting with corresponding symptoms. In the past, these lesions have been treated with open surgical techniques. More recently, endovascular treatment approaches have been proposed for occlusive lesions in the innominate (IA) or common carotid (CCA) arteries. Retrograde stenting of IA and CCA lesions using flow reversal has been described in a retrospective case series; however, a modification of their technique is proposed. Case Presentation: The patient is a 68-year-old male with symptoms of right upper extremity claudication. CT angiogram revealed critical stenosis of the innominate artery and high-grade stenosis of the right subclavian artery. The patient consented to retrograde stenting of the innominate stenosis with neuroprotection using flow reversal or transcarotid revascularization (TCAR) in reverse. Surgical cut-down was performed of the carotid bifurcation, and a U-stitch was placed on the anterior wall of the distal common carotid artery. Flow reversal was achieved by connecting the arterial sheath to the venous sheath. The innominate lesion was crossed, primarily stented with a VBX stent, and post-dilated with a non-compliant balloon. Just prior to crossing the lesion and primary stent placement, the vessel loop around the common carotid and internal carotid arteries were pulled up to ensure neuroprotection while the stent was expanded. This was continued for two minutes before restoring antegrade flow first in the external carotid and then in the internal carotid artery. There were no adverse events. At one month follow-up, the patient reported no right arm claudication symptoms. TCAR for the proximal lesion as described in other case series may not adequately attain flow based neuroprotection. Under that circumstance, the arterial sheath is acting as a conduit to deliver the stent. Risk of embolization to the brain may not be mitigated when the proximal lesion is stented and antegrade flow restored.

Angioplasty versus stenting for subclavian artery stenosis

BACKGROUND

The subclavian arteries are two major arteries of the upper chest, below the collar bone, which come from the arch of the aorta. Endovascular treatment for stenosis of the subclavian arteries includes angioplasty alone, and with stenting. There is insufficient evidence to guide the use of stents following angioplasty for subclavian artery stenosis. This is the second update of a review first published in 2011.

OBJECTIVES

The aim of this review was to determine whether stenting was more effective than angioplasty alone for stenosis of the subclavian artery.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and LILACS databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 2 February 2021.

SELECTION CRITERIA

We searched for randomised controlled trials of endovascular treatment of subclavian artery lesions that compared angioplasty alone and stent implantation.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated studies to assess eligibility. Discrepancies were resolved by discussion. If there was no agreement, we asked a third review author to assess the study for inclusion. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions, and assess the certainty of the evidence using a GRADE approach.

MAIN RESULTS

To date, we have not identified any completed or ongoing randomised controlled trials that compare percutaneous transluminal angioplasty and stenting for subclavian artery stenosis.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine whether stenting is more effective than angioplasty alone for stenosis of the subclavian artery.

Color Doppler Ultrasonography for the Evaluation of Subclavian Artery Stenosis

BACKGROUND

It is of great significance to evaluate symptomatic subclavian artery (SA) stenosis by color Doppler ultrasonography. More than 50% SA stenosis may induce symptoms. Currently, there is a paucity of published literature and lack of practitioner consensus for how ultrasonic findings should be interpreted in patients with SA stenosis.

OBJECTIVE

The study aimed to prospectively evaluate SA stenosis using color Doppler ultrasonography, with digital subtraction angiography as a reference. Moreover, we aimed to determine the optimal thresholds to predict SA stenosis (≥50%).

METHODS

A total of 423 SAs from 234 patients with normal or stenotic lumen were enrolled. The peak systolic velocity (PSV) and acceleration time at the stenotic and distal segments of the SA, peak reversed velocity of the vertebral artery, and waveforms of the stenotic SA, distal SA, and vertebral artery were recorded. The ratios of stenotic PSV to distal PSV (PSVr) and distal AT to stenotic AT were also calculated. The optimal cutoff values were determined using receiver operating characteristic analysis.

RESULTS

All ultrasonic parameters were significantly correlated with the degree of SA stenosis, whereas PSV (r = 0.624, P < 0.001), PSVr (r = 0.654, P < 0.001) and VA waveform change (r = 0.631, P < 0.001) had the strongest correlation with SA stenosis. The optimal cutoff values were as follows: PSV ≥ 230 cm/s and PSVr ≥ 2.2 to predict ≥ 50% stenosis, and PSV ≥ 340 cm/s and PSVr ≥ 3.0 to predict ≥ 70% stenosis.

CONCLUSIONS

Symptomatic patients with the ultrasonic parameters of PSV ≥ 230 cm/s and PSVr ≥ 2.2 need to be considered for further verification by computed tomographic angiography or magnetic resonance angiography, or by digital subtraction angiography with a view to percutaneous transluminal angioplasty/stent implantation in the same session. The recommended graded cutoff values can help in long-term management of patients with SA stenosis.

One-Year Change in Walking Performance and Subsequent Mobility Loss and Mortality Rates in Peripheral Artery Disease: Longitudinal Data From the WALCS

Background Associations of 1-year change in functional performance measures with subsequent mobility loss and mortality in people with lower extremity peripheral artery disease are unknown. Methods and Results Six-minute walk and 4-meter walking velocity (usual and fastest pace) were measured at baseline and 1 year later in 612 people with peripheral artery disease (mean age 71±9 years, 37% women). Participants were categorized into tertiles, based on 1-year changes in walking measures. Cox proportional hazards models were used to examine associations between 1-year change in each walking measure and subsequent mobility loss and mortality, respectively, adjusting for potential confounders. Compared with the best tertile, the worst tertile (ie, greatest decline) in 1-year change in each performance measure was associated with higher rates of mobility loss: 6-minute walk (Tertile 1 [T1] cumulative incidence rate [IR], 72/160; Tertile 3 [T3] IR, 47/160; hazard ratio [HR], 2.35; 95% CI, 1.47-3.74), usual-paced 4-meter walking velocity (T1 IR, 54/162; T3 IR, 57/162; HR, 2.21; 95% CI, 1.41-3.47), and fast-paced 4-meter walking velocity (T1 IR, 61/162; T3 IR, 58/162; HR, 1.81; 95% CI, 1.16-2.84). Compared with the best tertile, the worst tertiles in 1-year change in 6-minute walk (T1 IR, 66/163; T3 IR, 54/163; HR, 1.61; 95% CI, 1.07-2.43) and fast-paced 4-meter walking velocity (T1 IR, 63/166; T3 IR, 44/166; HR, 1.75; 95% CI, 1.16, 2.64) were associated with higher mortality. Conclusions In people with peripheral artery disease, greater 1-year decline in 6-minute walk or 4-meter walking velocity may help identify people with peripheral artery disease at highest risk for mobility loss and mortality.

Prevalence and Clinical Characteristics of Subclavian Steal Phenomenon/Syndrome in Patients with Acute Ischemic Stroke

There are no published clinical studies regarding the prevalence of subclavian steal among acute ischemic stroke patients. The aim of this study was to evaluate the prevalence and clinical significance of subclavian steal among a large number of consecutive ischemic stroke patients. Materials and methods: We reviewed the medical records of 2192 consecutive cases of acute ischemic stroke at a tertiary neurology clinic in Targu Mures, Romania, between 2018 and 2020. In total, 47 patients (2.2%) were diagnosed with subclavian steal phenomenon/syndrome. Results: Stroke patients with associated steal phenomenon were significantly younger (64.2 ± 11.1 versus 70.2 ± 12.8, p = 0.005) and predominantly male (68.1%). From among the 47 patients with subclavian steal phenomenon, nine (19.1%) presented stroke symptomatology in the vertebrobasilar territory. Overall, 83.3% of the stroke patients with associated steal phenomenon presented cerebral infarction and 16.7% presented TIA. There was no difference between groups regarding the affected vascular territory (VB versus carotid). Large artery atherosclerosis was more frequent in the stroke group with associated steal phenomenon (81.3% versus 43.5%, p = 0.0033). The NIHSS score at admission was higher in the patient group with associated steal phenomenon, but there was no difference in mRS at discharge. Associated carotid artery occlusion was more frequent in the stroke group with steal phenomenon (p < 0.01). Smoking and peripheral arteriopathy were more frequent in the patient group with associated steal phenomenon. Of the nine symptomatic patients, five underwent revascularization treatment. Conclusions: The prevalence of subclavian steal phenomenon among acute ischemic stroke patients was not higher than in other cohorts with heterogenous peripheral vascular pathologies. Similar to the general population, in acute ischemic stroke patients, the associated subclavian steal behaved like a benign hemodynamical condition, without severe consequences.

A physiologically realistic virtual patient database for the study of arterial haemodynamics

This study creates a physiologically realistic virtual patient database (VPD), representing the human arterial system, for the primary purpose of studying the effects of arterial disease on haemodynamics. A low dimensional representation of an anatomically detailed arterial network is outlined, and a physiologically realistic posterior distribution for its parameters constructed through the use of a Bayesian approach. This approach combines both physiological/geometrical constraints and the available measurements reported in the literature. A key contribution of this work is to present a framework for including all such available information for the creation of virtual patients (VPs). The Markov Chain Monte Carlo (MCMC) method is used to sample random VPs from this posterior distribution, and the pressure and flow-rate profiles associated with each VP computed through a physics based model of pulse wave propagation. This combination of the arterial network parameters (representing a virtual patient) and the haemodynamics waveforms of pressure and flow-rates at various locations (representing functional response and potential measurements that can be acquired in the virtual patient) makes up the VPD. While 75,000 VPs are sampled from the posterior distribution, 10,000 are discarded as the initial burn-in period of the MCMC sampler. A further 12,857 VPs are subsequently removed due to the presence of negative average flow-rate, reducing the VPD to 52,143. Due to undesirable behaviour observed in some VPs-asymmetric under- and over-damped pressure and flow-rate profiles in left and right sides of the arterial system-a filter is proposed to remove VPs showing such behaviour. Post application of the filter, the VPD has 28,868 subjects. It is shown that the methodology is appropriate by comparing the VPD statistics to those reported in literature across real populations. Generally, a good agreement between the two is found while respecting physiological/geometrical constraints.

A proof of concept study for machine learning application to stenosis detection

This proof of concept (PoC) assesses the ability of machine learning (ML) classifiers to predict the presence of a stenosis in a three vessel arterial system consisting of the abdominal aorta bifurcating into the two common iliacs. A virtual patient database (VPD) is created using one-dimensional pulse wave propagation model of haemodynamics. Four different machine learning (ML) methods are used to train and test a series of classifiers—both binary and multiclass—to distinguish between healthy and unhealthy virtual patients (VPs) using different combinations of pressure and flow-rate measurements. It is found that the ML classifiers achieve specificities larger than 80% and sensitivities ranging from 50 to 75%. The most balanced classifier also achieves an area under the receiver operative characteristic curve of 0.75, outperforming approximately 20 methods used in clinical practice, and thus placing the method as moderately accurate. Other important observations from this study are that (i) few measurements can provide similar classification accuracies compared to the case when more/all the measurements are used; (ii) some measurements are more informative than others for classification; and (iii) a modification of standard methods can result in detection of not only the presence of stenosis, but also the stenosed vessel.

Graphical Abstract

Diagnosis and management of unilateral subclavian steal syndrome with bilateral carotid artery stenosis

Subclavian steal syndrome is a rare phenomenon occurring from retrograde blood flow in the vertebral artery due to proximal stenosis in the subclavian artery. As a result, the arm gets blood supply from the vertebral artery at the expense of the vertebrobasilar system. The patient remains largely asymptomatic until there is an increase demand for blood supply to the arm, resulting in a constellation of symptoms including dizziness, vertigo, blurred vision, diplopia, headache, syncope, postural hypotension, neurologic deficits, and rarely, memory problems. The management approach depends on the severity of clinical symptoms but includes medical treatment, endovascular therapy and lifestyle modifications.

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Subclavian steal syndrome with concurrent carotid artery stenosis is only the second documented case, which makes it an extremely rare presentation or frequently unnoticed condition.

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Absence of symptoms does not rule out subclavian steal syndrome with bilateral carotid stenosis and should be considered in the differential in patients with high risk comorbidities with appropriate imaging and physical exam.

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The treatment depends on the severity of clinical symptoms but includes medical treatment, endovascular therapy and lifestyle modifications.

Extent and progression of atherosclerosis in carotid and subclavian arteries: the Carotid Artery Subclavian Artery study

AIMS

To define the prevalence, progression, and the relationship between carotid and subclavian artery atherosclerosis and to identify factors associated with disease progression in a population of asymptomatic patients.

METHODS

Among all consecutive patients without a history of cardiovascular disease admitted to our hospital for duplex ultrasound examinations of the supra-aortic arteries, from January to December 2012, we retrospectively identified 530 patients with two evaluations at least 3 years apart. Each artery was graded according to stenosis degree, as absent or less than 20%, 20-49%, 50-69%, 70-99% and total occlusion. Disease progression was defined for any class increase at any time interval. Patients were grouped according to the presence of a more than 20% stenosis of the supra-aortic district at baseline, as controls, without atherosclerosis: n = 111, 21%; isolated carotid artery disease: n = 390, 74%; concomitant subclavian artery-carotid artery disease: n = 29, 5%. There were no cases with isolated subclavian artery atherosclerosis.

RESULTS

The mean time-lapse between the two evaluations was 3.1 ± 0.3 years; we documented disease progression in 32 patients (6%), all limited to the carotid artery (P = 0.009 vs. controls, with no differences between isolated carotid artery disease and concomitant carotid and subclavian artery disease). Hypertension was significantly (P < 0.001) associated with disease progression, regardless of the single or double district involvement.

CONCLUSION

The subclavian artery is far less prone to atherosclerosis than the carotid artery, and features lesser disease progression. Understanding factors for the different susceptibility to atherosclerosis in these two close arterial districts provides insight into local factors prompting vascular disease.

Machine learning for detection of stenoses and aneurysms: application in a physiologically realistic virtual patient database

This study presents an application of machine learning (ML) methods for detecting the presence of stenoses and aneurysms in the human arterial system. Four major forms of arterial disease-carotid artery stenosis (CAS), subclavian artery stenosis (SAS), peripheral arterial disease (PAD), and abdominal aortic aneurysms (AAA)-are considered. The ML methods are trained and tested on a physiologically realistic virtual patient database (VPD) containing 28,868 healthy subjects, adapted from the authors previous work and augmented to include disease. It is found that the tree-based methods of Random Forest and Gradient Boosting outperform other approaches. The performance of ML methods is quantified through the [Formula: see text] score and computation of sensitivities and specificities. When using six haemodynamic measurements (pressure in the common carotid, brachial, and radial arteries; and flow-rate in the common carotid, brachial, and femoral arteries), it is found that maximum [Formula: see text] scores larger than 0.9 are achieved for CAS and PAD, larger than 0.85 for SAS, and larger than 0.98 for both low- and high-severity AAAs. Corresponding sensitivities and specificities are larger than 90% for CAS and PAD, larger than 85% for SAS, and larger than 98% for both low- and high-severity AAAs. When reducing the number of measurements, performance is degraded by less than 5% when three measurements are used, and less than 10% when only two measurements are used for classification. For AAA, it is shown that [Formula: see text] scores larger than 0.85 and corresponding sensitivities and specificities larger than 85% are achievable when using only a single measurement. The results are encouraging to pursue AAA monitoring and screening through wearable devices which can reliably measure pressure or flow-rates.

Prevalence and characteristics of atherosclerotic plaque: Left compared with right arteries and anterior compared with posterior circulation stroke

PURPOSE

To evaluate atherosclerotic plaque prevalence and characteristics between left and right cervicocephalic arteries and between anterior and posterior circulation stroke (ACS and PCS).

METHODS

This retrospective study included 284 patients with acute ischemic stroke (199 ACS and 85 PCS) involving large-artery atherosclerosis or small-artery occlusion. We assessed atherosclerotic plaque prevalence and characteristics (plaque type, plaque surface morphology, plaque distribution, location of calcified nodules and plaque thickness) in each segment and their comparisons between left and right arteries and between ACS and PCS.

RESULTS

The left subclavian artery (L-SA), common carotid artery (L-CCA) and intracranial vertebral artery (L-IVA) had significantly higher prevalence of atherosclerotic plaque than the right (R) corresponding arteries (70.1% versus 59.5%, P = 0.008), (48.1% versus 28.9%, P < 0.001), (23.9% versus 16%, P = 0.018), respectively. L-SA had a higher prevalence of mixed plaque (non-calcified > calcified) (19.6% versus 16.4%) and noncalcified plaque (51.9% versus 31.7%), and a lower prevalence of calcified plaque (8.9% versus 23.3%) and mixed plaque (calcified > non-calcified) (19.6% versus 28.6%) than R-SA, P < 0.001. The distribution of plaque type in the SA and extracranial vertebral artery (EVA) were significantly different between ACS and PCS. The soft plaque thickness of SA in PCS was significantly greater than that in ACS (3.85 ± 1.27 versus 3.51 ± 1.04, P = 0.032).

CONCLUSIONS

Atherosclerotic plaque prevalence and characteristics vary in different segments, sides and between ACS and PCS. These differences should be noted during plaque diagnosis.

Unmasking the Coronary-Subclavian Steal Syndrome: The Culprit Lies in the Subclavian Artery. A Report of a Case and Review of the Literature

The coronary-subclavian steal syndrome is a hemodynamic phenomenon in which a subclavian artery stenosis or occlusion impairs blood flow at the origin of the left internal mammary artery used for coronary artery bypass grafting (CABG), causing retrograde blood flow and thus provoking symptoms of cardiac ischemia and its complications. Once considered the gold-standard operation of choice, open revascularization has now been abandoned as a first line treatment and replaced by endovascular techniques. In all cases, detailed and oriented physical examination in combination with further imaging in high clinical suspicion for coronary-subclavian steal syndrome remains the sine qua non of the preoperative examination of the patient. We report the case of a 50-year-old male patient suffering from acute onset angina post- coronary artery bypass grafting and managed by endovascular means.

Endovascular treatment of coronary subclavian steal syndrome: a case series highlighting the diagnostic usefulness of a multimodality imaging approach

Background

Coronary subclavian steal syndrome (CSSS) is an uncommon complication observed in patients after coronary artery bypass surgery with left internal mammary artery (LIMA) grafts. It is defined as coronary ischaemia due to reversal flow from the LIMA to the left subclavian artery (SA) when a proximal left SA stenosis is present. In practice, the entire clinical spectrum of ischaemic heart disease, ranging from asymptomatic patients to acute myocardial infarction, may be encountered.

Case summary

Three cases of CSSS recently detected at our hospital are being described. Two patients presented with an acute coronary syndrome, so diagnosis was suspected based on coronary angiography findings, as retrograde blood flow from LIMA to the distal SA was present. Myocardial ischaemia was documented by myocardial perfusion scintigraphy in one case. The third patient was asymptomatic and CSSS was suspected during physical examination and confirmed by computed tomography (CT). Endovascular intervention with balloon-expandable stent implantation of the stenotic SA was performed by vascular surgeons in all patients. No periprocedural complications occurred, and complete resolution of symptoms was achieved.

Discussion

In CSSS, subclavian angiography is the standard diagnostic test. However, other diagnostic techniques may be valuable to better clarify this challenging diagnosis. In the herein small series, the usefulness of a multimodality imaging approach including Doppler ultrasound, myocardial perfusion scintigraphy, and CT is well demonstrated. Furthermore, this study endorses the safety and utility of endovascular treatment in different clinical scenarios, including asymptomatic patients.

Brachiocephalic and subclavian stenosis: Current concepts for cardiovascular specialists

Brachiocephalic and subclavian artery stenoses are less common manifestations of peripheral arterial disease (PAD) compared to lower extremity PAD. However, even among asymptomatic patients, a diagnosis of PAD portends worse long-term mortality. Symptoms may include subclavian steal syndrome and arm claudication. Among patients with internal mammary coronary bypass grafts, symptoms may include those of myocardial ischemia. Symptomatic subclavian stenosis can be readily treated using endovascular techniques with durable outcomes.

Clinical characteristics and response to supervised exercise therapy of people with lower extremity peripheral artery disease

BACKGROUND

Among people with lower extremity peripheral artery disease (PAD), little is known about variation in response to supervised exercise therapy (SET). Clinical characteristics associated with greater responsiveness to SET have not been identified.

METHODS

Data from participants with PAD in two randomized clinical trials comparing SET vs nonexercising control were combined. The exercise intervention consisted of three times weekly supervised treadmill exercise. The control groups received lectures on health-related topics.

RESULTS

Of 309 unique participants randomized (mean age, 67.9 years [standard deviation, 9.3 years]; 132 [42.7%] women; 185 [59.9%] black), 285 (92%) completed 6-month follow-up. Compared with control, those randomized to SET improved 6-minute walk distance by 35.6 meters (95% confidence interval, 21.4-49.8; P < .001). In the 95 (62.1%) participants who attended at least 70% of SET sessions, change in 6-minute walk distance varied from -149.4 to +356.0 meters. Thirty-four (35.8%) had no 6-minute walk distance improvement. Among all participants, age, sex, race, body mass index, prior lower extremity revascularization, and other clinical characteristics did not affect the degree of improvement in 6-minute walk distance after SET relative to the control group. Participants with 6-minute walk distance less than the median of 334 meters at baseline had greater percentage improvement in 6-minute walk distance compared with those with baseline 6-minute walk distance above the median (+20.5% vs +5.3%; P for interaction = .0107).

CONCLUSIONS

Among people with PAD, substantial variability exists in walking improvement after SET. Shorter 6-minute walk distance at baseline was associated with greater improvement after SET, but other clinical characteristics, including age, sex, prior lower extremity revascularization, and disease severity, did not affect responsiveness to exercise therapy.

Long-term Outcome of Axillo-axillary Bypass in Patients with Subclavian or Innominate Artery Stenosis

BACKGROUND

Subclavian or innominate artery stenosis (SAS) may cause upper extremity and cerebral ischemia. In patients with symptomatic subclavian or innominate artery stenosis, percutaneous transluminal angioplasty is the treatment of first choice. When percutaneous transluminal angioplasty is technically restricted or unsuccessful, an extrathoracic bypass grafting, such as an axillo-axillary bypass can be considered. The patency rate of axillo-axillary bypass is often questioned. The aim of this study was to assess long-term outcomes of patients undergoing axillo-axillary bypass for subclavian or innominate artery stenosis (SAS) and to provide a literature overview.

METHODS

In this single-center study, data from patients who underwent axillo-axillary bypass for symptomatic SAS between 2002 and 2018 were retrospectively analyzed. Bypass material was Dacron® (54%) or polytetrafluoroethylene (PTFE) (46%). Primary outcome was graft patency and secondary outcome was the occurrence of mortality and stroke. In addition, a systematic literature search was performed in MEDLINE and EMBASE databases including all studies describing patency of axillo-axillary bypass.

RESULTS

In total, 28 axillo-axillary bypasses had been performed. Cumulative primary, primary-assisted, and secondary patency rates at one year were 89%, 93%, and 96%, respectively. Cumulative primary, primary-assisted, and secondary patency rates at five years were 76%, 84%, and 87%, respectively. The primary-assisted patency rates at five years for Dacron® and PTFE were 93% and 73%, respectively. A total of four primary axillo-axillary bypass occlusions occurred (14%), with a mean of 12 months (range, 0.4-25) after operation. The 30-day mortality was 7%; one patient died after a stroke and one died of a myocardial infarction. At the first postoperative follow-up control, 22 of the 26 remaining patients (85%) had relief of symptoms. The literature search included 7 studies and described a one-year primary patency range of 93-100% (n = 137) and early postoperative adverse events included death (range, 0-13%) and stroke (range, 0-5%).

CONCLUSIONS

Patency rates of axillo-axillary bypasses for patients with a symptomatic SAS are good. However, the procedural complication rate in this series is high and attention should be paid to intervention indication.

Mitochondrial DNA damage in calf skeletal muscle and walking performance in people with peripheral artery disease

BACKGROUND

Peripheral artery disease (PAD) is associated with mitochondrial dysfunction in calf skeletal muscle and a greater abundance of mitochondrial DNA (mtDNA) heteroplasmy. However, it is unknown whether calf skeletal muscle mtDNA of PAD participants harbors a greater abundance of mitochondrial DNA 4977-bp common deletion (mtDNA⁴⁹⁷⁷), strand breaks and oxidative damage (i.e., oxidized purines) compared to non-PAD participants and whether these mtDNA abnormalities are associated with poor walking performance in participants with PAD.

METHODS

Calf muscle biopsies were obtained from 50 PAD participants (ankle-brachial index (ABI) < 0.95) and 25 non-PAD participants (ABI = 0.99-1.40) matched by age, sex, and race. The abundance of mtDNA copy number, mtDNA⁴⁹⁷⁷ deletion, strand breaks, and oxidized purines in selected mtDNA regions coding for electron transport chain (ETC) constituents and the non-coding D-Loop region was determined in calf muscle. All participants completed measurement of 6-min walk and usual and fast-paced 4-m walking velocity test.

RESULTS

Participants with PAD (mean age = 65.4 years, SD = 6.9; 14 (28%) women, 38 (76%) black) and without PAD (mean age = 65.2 years, SD = 6.7; 7 (28%) women, 16 (64%) black) did not differ in the abundance of calf muscle mtDNA⁴⁹⁷⁷ deletion, mtDNA strand breaks, and oxidized purines. Though, a greater abundance of mtDNA strand breaks within ND4/5 genes was significantly associated with poorer 6-min walk distance, lower usual-paced 4-m walking velocity, and lower fast-paced 4-m walking velocity in non-PAD participants. Significant associations were also found in the density of strand break damage (i.e., damage per mtDNA copy) within ND1/2, ND4/5 and COII/ATPase 6/8 region with 6-min walk distance, usual-paced 4-m walking velocity and fast-paced 4-m walking velocity in non-PAD participants. Significant interactions were found between PAD presence vs. absence and density of strand break damage within ND1/2, ND4/5, COII/ATPase 6/8 regions for the associations with 6-min walk distance, usual-paced 4-m walking velocity, fast-paced 4-m walking velocity. Conversely, of the three walking performance measures only the usual-paced 4-m walking velocity showed a significant, although modest, negative association with the abundance of oxidized purines in the D-Loop (P = 0.031) and ND4/5 (P = 0.033) regions in the calf skeletal muscle of people with PAD.

CONCLUSION

Overall, these data suggest that the abundance of calf muscle mtDNA strand breaks and mtDNA⁴⁹⁷⁷ common deletion are not associated with walking performance in people with PAD and may not be directly involved in the pathophysiology of PAD. Conversely, strand breaks in specific mtDNA regions may contribute to poor walking performance in people without PAD. Further study is needed to confirm whether usual-paced 4-m walking velocity is associated significantly with a greater abundance of oxidized purines in the D-loop, a "mutational hotspot" for oxidative damage, and why this association may differ from the association with 6-min walk distance and fast-paced 4-m walking velocity.

Prevalence and associated factors of inter-arm blood pressure difference in Chinese community hypertensive population

OBJECTIVES

This study aimed to investigate the prevalence and associated factors of inter-arm blood pressure difference (IAD) in Chinese community hypertensive population.

METHODS

The cross-sectional study included 7788 hypertensive patients (3673 male and 4115 female, aged 62.3 ± 13.6 years) in Guangdong, China. IAD was defined as the absolute value of blood pressure (BP) difference between left and right arms. Bilateral BP was measured simultaneously by automated devices.

RESULTS

The mean IAD was 4.04 ± 4.33 mm Hg in systolic and 3.19 ± 3.43 mm Hg in diastolic. The prevalence rates of systolic IAD (sIAD)≥5 mm Hg and ≥10 mmHg were 28.9% (n = 2247) and 12.8% (n = 996), respectively. By univariate linear regression, higher sIAD correlated with aging, higher SBP, higher DBP, lower baseline estimated glomerular filtration rate (eGFR), and anti-hypertensive medication (p < 0.05). In multivariate linear regression analysis, higher sIAD was significantly associated with systolic BP (SBP, β = 0.033; 95%CI, 0.025-0.041; p < 0.001), triacylglycerol (β = 0.093; 95%CI, 0.017-0.169; p = 0.016), total cholesterol (β = -0.202; 95%CI, -0.396to -0.009; p = 0.04), and low-density lipoprotein cholesterol (LDL-C; β = 0.304; 95%CI, 0.027-0.582; p = 0.032).

CONCLUSION

The elevated prevalence of large IAD was shown in hypertensive population. Meanwhile, higher levels of SBP, triacylglycerol, total cholesterol, LDL-C, and lower eGFR were associated with higher sIAD.