Coronary physiology thresholds associated with microvascular obstruction in myocardial infarction.

OBJECTIVES: To ascertain whether invasive assessment of coronary physiology soon after recanalisation of the culprit artery by primary percutaneous coronary intervention is associated with the development of microvascular obstruction by cardiac magnetic resonance in patients with ST-segment elevation myocardial infarction (STEMI). METHODS: Between November 2020 and December 2021, 102 consecutive patients were prospectively enrolled in five tertiary centres in Italy. Coronary flow reserve (CFR) and index of microvascular resistance (IMR) were measured in the culprit vessel soon after successful primary percutaneous coronary intervention. Optimal cut-off points of IMR and CFR to predict the presence of microvascular obstruction were estimated, stratifying the population accordingly in four groups. A comparison with previously proposed stratification models was carried out. RESULTS: IMR>31 units and CFR≤1.25 yielded the best accuracy. Patients with IMR>31 and CFR≤1.25 exhibited higher microvascular obstruction prevalence (83% vs 38%, p<0.001) and lower left ventricular ejection fraction (45±9% vs 52±9%, p=0.043) compared with those with IMR≤31 and CFR>1.25, and lower left ventricular ejection fraction compared with patients with CFR≤1.25 and IMR≤31 (45±9% vs 54±7%, p=0.025). Infarct size and area at risk were larger in the former, compared with other groups. CONCLUSIONS: IMR and CFR are associated with the presence of microvascular obstruction in STEMI. Patients with an IMR>31 units and a CFR≤1.25 have higher prevalence of microvascular obstruction, lower left ventricular ejection fraction, larger infarct size and area at risk. TRIAL REGISTRATION NUMBER: NCT04677257.

Cardiac magnetic resonance predictors of left ventricular remodelling following acute ST elevation myocardial infarction: The VavirimS study.

BACKGROUND: Left ventricular (LV) remodelling (REM) ensuing after ST-elevation myocardial infarction (STEMI), has typically been studied by echocardiography, which has limitations, or cardiac magnetic resonance (CMR) in early phase that may overestimate infarct size (IS) due to tissue edema and stunning. This prospective, multicenter study investigated LV-REM performing CMR in the subacute phase, and 6 months after STEMI. METHODS AND RESULTS: patients with first STEMI undergoing successful primary angioplasty were consecutively enrolled. CMR was done at 30-days and 6-months. Primary endpoint was prevalence at 6 months of LV-REM [≥12% increase in LV end-diastolic volume index (LV-REMEDV)]; LV-REM by end-systolic volume index increase ≥12% (LV-REMESV) was also calculated. Of 325 patients enrolled, 193 with a full set of research-quality CMR images were analyzed. LV-REMEDV and LV-REMESV were present in 36/193 (19%) and 34/193 (18%) patients, respectively. At follow up, LV ejection fraction (EF) improved in patients with or without LV-REMEDV, whilst it decreased in those with LV-REMESV (p < 0.001 for interaction). Considering predictors of LV-REM, IS in the highest tertile was clearly separated from the two lower tertiles. In LV-REMEDV, the highest tertile was associated with significantly higher LV-EDV, LV-ESV, and lower EF. CONCLUSIONS: In a contemporary cohort of STEMI patients studied by CMR, prevalence of LV-REMEDV was lower than previously reported. Importantly, our data indicate that LV-REMEDV might not be "adverse" per se, but rather "compensatory", being associated with LV-EF improvement at follow-up. Conversely, LV-REMESV might be an "adverse" phenomenon associated with decreased LV-EF, driven by IS.

Results of a prospective observational study of autologous peripheral blood mononuclear cell therapy for no-option critical limb-threatening ischemia and severe diabetic foot ulcers.

BACKGROUND: Cell therapy with autologous peripheral blood mononuclear cells (PB-MNCs) may help restore limb perfusion in patients with diabetes mellitus and critical limb-threatening ischemia (CLTI) deemed not eligible for revascularization procedures and consequently at risk for major amputation (no-option). Fundamental is to establish its clinical value and to identify candidates with a greater benefit over time. Assessing the frequency of PB circulating angiogenic cells and extracellular vesicles (EVs) may help in guiding candidate selection. METHODS: We conducted a prospective, non-controlled, observational study on no-option CLTI diabetic patients that underwent intramuscular PB-MNCs therapy, which consisted of more cell treatments repeated a maximum of three times. The primary endpoint was amputation rate at 1 year following the first treatment with PB-MNCs. We evaluated ulcer healing, walking capability, and mortality during the follow-up period. We assessed angiogenic cells and EVs at baseline and after each cell treatment, according to primary outcome and tissue perfusion at the last treatment [measured as transcutaneous oxygen pressure (TcPO2)]. RESULTS: 50 patients were consecutively enrolled and the primary endpoint was 16%. TcPO2 increased after PB-MNCs therapy (17.2 ± 11.6 vs 39.1 ± 21.8 mmHg, p < .0001), and ulcers healed with back-to-walk were observed in 60% of the study population (88% of survivors) during follow-up (median 1.5 years). Patients with a high level of TcPO2 (≥ 40 mmHg) after the last treatment showed a high frequency of small EVs at enrollment. CONCLUSIONS: In no-option CLTI diabetic patients, PB-MNCs therapy led to an improvement in tissue perfusion, a high rate of healing, and back-to-walk. Coupling circulating cellular markers of angiogenesis could help in the identification of patients with a better clinical benefit over time.

Chimney Stenting for Coronary Occlusion During TAVR: Insights From the Chimney Registry.

OBJECTIVES: The aim of this study was to determine the safety and efficacy of chimney stenting, a bailout technique to treat coronary artery occlusion (CAO). BACKGROUND: CAO during transcatheter aortic valve replacement (TAVR) is a rare but often fatal complication. METHODS: In the international Chimney Registry, patient and procedural characteristics and data on outcomes are retrospectively collected from patients who underwent chimney stenting during TAVR. RESULTS: To date, 16 centers have contributed 60 cases among 12,800 TAVR procedures (0.5%). Chimney stenting was performed for 2 reasons: 1) due to the development of an established CAO (n = 25 [41.6%]); or 2) due to an impending CAO (n = 35 [58.3%]). The majority of cases (92.9%) had 1 or more classical risk factors for CAO. Upfront coronary protection was performed in 44 patients (73.3%). Procedural and in-hospital mortality occurred in 1 and 2 patients, respectively. Myocardial infarction (52.0% vs. 0.0%; p < 0.01), cardiogenic shock (52.0% vs. 2.9%; p < 0.01), and resuscitation (44.0% vs. 2.9%; p < 0.01) all occurred more frequently in patients with established CAO compared with those with impending CAO. The absence of upfront coronary protection was the sole independent risk factor for the combined endpoint of death, cardiogenic shock, or myocardial infarction. During a median follow-up time of 612 days (interquartile range: 405 to 842 days), 2 cases of stent failure were reported (1 in-stent restenosis, 1 possible late stent thrombosis) after 157 and 374 days. CONCLUSIONS: Chimney stenting appears to be an acceptable bailout technique for CAO, with higher event rates among those with established CAO and among those without upfront coronary protection.

Comparison of SFA lesion treatment with Zilver PTX in diabetics vs. non-diabetics: 2-year clinical and functional results.

BACKGROUND: Prospective single-arm study, aimed at evaluating safety and effectiveness at 12 and 24 months of the paclitaxel-eluting nitinol stent (Zilver PTX), and focused in particular on the treatment of complex lesions and/or diabetic patients. METHODS: Between May 2010 and March 2012, 67 patients (78% males) were treated by Zilver PTX, because of stenosis or occlusions of the superficial femoral artery in one of two centers. The mean age of patients was 70.1±8 years. Thirty-two of 67 (48%) were diabetics, 14 (21%) active smokers and 11 (14.6%) had chronic renal failure (end stage renal disease). The average length of lesions was 104±60 mm. Occlusion was complete in 46.3% of cases, whereas severely calcified lesions were present in 30% of patients (18.8% in diabetics and 31.4% in non-diabetics). Twenty-six patients (39%) had type C or D lesions according to TASC 2. RESULTS: One hundred-two stents were used (1.7±0.9 per patients); median 1 (range 1-4). All patients had successful stent placement. Primary patency, evaluated by Kaplan-Meier method was 88±0.06% at 12 months, and 68±0.1% at 24 months. In particular, the difference between diabetics (D) and non-diabetics (non-D) was not significant (P=0.07, Log-Rank). Patients turned from 4.2±1.3 to 1.6±1.3 Rutherford class. There were 5 deaths due to systemic comorbidities. There also were 3 major amputations, all of them also in the D group. Among the other patients, differences between D and non-D patients were not significant in terms of wound healing, bipedal stay and spontaneous ambulation. The mean follow-up length was 28±5 months (range 24-36 months). There was only one patient who had fracture and stent migration (1.5%). In 13 diabetic patients, tibial PTA was also associated. Additional treatment was required in 6 D and 1 non-D. CONCLUSIONS: The use of Zilver PTX is safe and effective in the treatment of SFA lesions. In particular, both stent patency and functional results on the basis of both clinical and instrumental tools were similar in D and non-D, suggesting a particularly favorable activity of PTX in a subpopulation of diabetics. Further studies are required to confirm these results, which seem to be particularly promising in diabetic patients.

Transcatheter CoreValve implantation for aortic regurgitation in a Jehovah's witness with prior aortic dissection.

Indications for transcatheter valve implantation have been extended to treat native valve aortic regurgitation in case of disproportionate risk for open surgery. Transcatheter aortic valves are also an attractive alternative in patients who refuse blood transfusions. We report the successful off-label implantation of a self-expandable transcatheter valve in a Jehovah's Witness with prior replacement of the ascending aorta for Type A dissection, residual severe aortic regurgitation and refractory heart failure.

Valvulopathies in sub-Saharan African children: patterns, humanitarian interventions and cardiac surgical problems.

Despite the high burden of rheumatic fever in sub-Saharan African, there is currently no sustained and comprehensive strategy to control the disease. Consequently in this area the number of patients affected by rheumatic valve disease (RVD), most with a surgical indication, is 10-20 fold higher than in industrialised countries and estimates indicate that more than 50% of African RVD patients will die before age 25. In this paper, we review clinical and management issues of RVD in children in sub-Saharan Africa. Severe heart failure and undergrowth are the prevalent presentation of the illness. Severe mitral regurgitation is the commonest rheumatic valvulopathy observed in the first and second decades. Valve repair, the approach of choice, may be associated with unfavourable outcomes in patients with extreme cardiomegaly. In young people, whenever correct anticoagulation may reasonably be achieved, mechanical mitral prostheses should be preferred, even in females. The early deterioration of biologic mitral prostheses strongly suggests limiting their use to those cases in which correct anticoagulation is not feasible. In most sub-Saharan countries, socioeconomic factors strongly limit access to health services and to cardiac surgery in particular. Efforts to overcome these barriers have resulted in humanitarian projects along two patterns: creation of high tech on site health care structures or transfer of children with complex diseases to receive highly specialised cardiac surgical care abroad. We summarise the experience of our programme that followed the latter approach.

Revascularization by angioplasty of type D femoropopliteal and long infrapopliteal lesion in diabetic patients with critical limb ischemia: are TASC II recommendations suitable? A population-based cohort study.

Feasibility of revascularization of type D femoropopliteal and long infrapopliteal lesions by angioplasty (peripheral translumenal angioplasty [PTA]) in diabetic patients with critical limb ischemia (CLI) according to the TransAtlantic Inter-Society Consensus (TASC) II recommendations was studied. A total of 292 diabetic patients were admitted for CLI; 308 limbs underwent a PTA. Out of 211 femoropopliteal lesions treated with PTA, 44 were TASC II type A, 45 type B, 48 type C, and 76 type D lesions. In 44 of the 76 patients with type D lesions revascularized by PTA, no artery was patent down to the foot before the PTA. In 172 limbs with all infrapopliteal arteries occluded, revascularization was carried out down to the foot in 167 limbs. Follow-up was 3.1 ± 0.3 years. A first episode of restenosis occurred in 66/308 limbs with an incidence/year of 7.9. PTA procedures were successfully repeated in 57/66 restenosis episodes: secondary patency was 97.1%. The incidence/year of type D femoropopliteal lesions was 5.4, the incidence/year in others was 5.0, without statistically significant differences: P = .417. The only variable found significantly associated with restenosis occurrence on logistic analysis was the presence of lesions in both femoropopliteal and infrapopliteal axes. A total of 26/308 above-the-ankle amputations were performed, with an incidence/year of 2.5. Multivariate analysis showed the independent role of only crural artery occlusion after PTA. These data show that the choice to refer to angioplasty diabetic patients with type D and/or long infrapopliteal lesions without good run-off at the foot and/or high surgical risk allowed high revascularization feasibility, with an optimal amputation outcome.

Limb revascularization feasibility in diabetic patients with critical limb ischemia: results from a cohort of 344 consecutive unselected diabetic patients evaluated in 2009.

AIMS: To evaluate the feasibility of peripheral revascularization by angioplasty (PTA) or bypass grafting (BPG) in diabetic patients with critical limb ischemia (CLI). METHODS: All diabetic patients referred to our Diabetic Foot Centre for foot lesion or rest pain were assessed for the presence of CLI as assessed by the TASC criteria. All patients underwent angiography that was evaluated jointly by an interventional radiologist, a vascular surgeon and a diabetologist of the diabetic foot care team. RESULTS: During 2009, 344 diabetics were admitted because of CLI in a total of 360 limbs. PTA was performed in 308 (85.6%) limbs, and BPG was performed in 40 (11.1%) limbs in which PTA was not feasible. Revascularization could not be carried out in 12 (3.3%) limbs due to the lack of target vessel (9 limbs) or high surgical risk (3 limbs). According to the judgement of the vascular surgeon, BPG was anatomically feasible in 180 (58.4%) of the 308 limbs that underwent PTA. Therefore, considering also the 40 limbs that underwent BPG, surgical revascularization was judged anatomically possible in a total of 220 (61.1%) limbs. At 30 days, 19 (5.3%) above-the-ankle amputations were performed: 8 (66.7%) amputations were performed in the 12 non-revascularized limbs, 8 (2.6%) amputations were performed in the 308 limbs treated with PTA and 3 (7.5%) amputations were performed in the 40 limbs treated with BPG. CONCLUSIONS: Revascularization by PTA is highly feasible in diabetics with CLI. The feasibility of revascularization by BPG is lower but nonetheless consistent. In centres where both revascularization procedures are available, it is possible to revascularize more than 96% of diabetics with CLI.

Antegrade approach for percutaneous interventions of ostial superficial femoral artery: outcomes from a prospective series of diabetic patients presenting with critical limb ischemia.

OBJECTIVES: This is a prospective evaluation of percutaneous interventions (PTAs) performed by the antegrade femoral approach in diabetic patients with critical limb ischemia (CLI) and ostial superficial femoral artery (SFA) lesions. METHODS: The puncture site was selected according to duplex scan analysis and physical examination (brachial, crossover, or antegrade). In cases of antegrade approach, a bare needle angiogram of the femoral bifurcation was performed in order to have an adequate distance (>2 cm) from the target lesion. RESULTS: Between January 2010 and August 2011, 64 diabetic patients underwent PTA for ostial SFA lesions. Crossover or brachial approach was electively adopted in 19/64 (30%) patients. The antegrade bare needle angiogram was performed in the remaining 45/64 (70%) patients. In two patients, the vascular anatomy was considered not suitable for antegrade approach, and they were treated in crossover. Technical success was achieved in 38/45 (84%) of patients. During hospital stay, one patient had SFA stent thrombosis treated with urgent bypass grafting. CONCLUSIONS: The antegrade approach can be safely performed in most patients presenting with CLI and ostial SFA lesions. The use of clinical and radiographic criteria correctly identifies patients with ostial SFA lesions suitable for an antegrade approach in 42/44 (95%) of cases.

CRosser As First choice for crossing Totally occluded coronary arteries (CRAFT Registry): focus on conventional angiography and computed tomography angiography predictors of success.

AIMS: We investigated the use of the CROSSER catheter, a CTO crossing device based upon high frequency mechanical vibration, as a first resort to treat patients with chronic total occlusions (CTO) while describing angiographic and computed tomography coronary angiography (CTCA) serving as predictors for success. METHODS AND RESULTS: Eighty consecutive patients were enrolled in this prospective multicentre registry of patients treated for a CTO. For 76.3% of the patients, this was the first attempt to open the CTO. Overall success rate was 75%. By conventional coronary angiography, the length of the occlusion was 26.7±14.1 mm and there was a difference in successful vs. unsuccessful cases (24.5±13.9 and 32.8±13.1, p=0.02). The presence of angulation, as defined qualitatively, was more prevalent in failed cases (60.0% vs. 32.2%, p=0.03). The mean ratio CROSSER distance within the occlusion site and length of the occlusion showed a trend towards statistical significance in successful procedures (0.56±0.90 vs. 0.30±0.34, p=0.08). During hospitalisation, two patients had a non-fatal myocardial infarction. One patient experienced delayed onset of tamponade six hours postprocedure. At 30 days, two patients had PCI in a non-treated vessel and one patient had a transient ischaemic attack. Relation to the CROSSER catheter was inconclusive. CONCLUSIONS: The success rate of the use of a dedicated-CTO device--the CROSSER catheter--as a first choice to open a chronic total occlusion was 75%. By multivariate analysis, in a subset of patients that were imaged with computed tomography coronary angiography, the absence of angulation was related with higher success rate.

A novel device for true lumen re-entry after subintimal recanalization of superficial femoral arteries: first-in-man experience and technical description.

Subintimal angioplasty (SAP) is frequently performed for the treatment of critical limb ischemia (CLI) and has been recognized as an effective technique for these patients. Nevertheless, this approach is limited by the lack of controlled re-entry into the true lumen of the target vessel. We describe a novel device for true lumen re-entry after subintimal recanalization of superficial femoral arteries (SFA). We report our experience with six patients treated between April 2009 and January 2010 with a novel system designed to facilitate true lumen re-entry. The device was advanced by ipsilateral antegrade approach through a 6-French sheath. Successful reaccess into the true lumen was obtained in five of six patients without complications. The patient in whom the reaccess to the true lumen was not possible underwent successful bypass surgery. At 30 days follow-up, the SFA was patent in all patients according to echo-Doppler examination. Our preliminary experience indicates that this novel re-entry device increases the success rate of percutaneous revascularization of chronically occluded SFA.