[IRM et myocardite infectieuse]. / IRM et myocardite infectieuse.

Over the past ten years, cardiac MRI has become an indispensable tool for acute myocarditis diagnosis. Under appropriate conditions, cardiac MRI may allow postponement of initial coronary angiography in many instances. The 2020 ESC guidelines give a class I recommendation to its use in the setting of MINOCA for differential diagnosis between acute myocardial infarction, myocarditis, Tako-Tsubo and other cardiac pathologies, in order to improve therapeutic management and follow-up. This article describes the technical characteristics of MRI in myocarditis (Lake Louise diagnostic criteria and criteria based on myocardial tissue mapping), the main differential diagnoses, the prognostic value and addresses the issue of myocarditis in the setting of COVID-19.

[TAVI in women, very encouraging results]. / TAVI chez les femmes, des résultats très encourageants.

The population of elderly patients comprises a high percentage of women. This population is more vulnerable due to the presence of numerous comorbidities and is, therefore, particularly exposed to the risk of aortic valve degeneration, resulting in aortic valve stenosis whose symptoms are predictors of poor short-term outcomes. In the presence of symptomatic aortic stenosis, the recommended therapeutic option in this vulnerable population is the implementation of transcatheter aortic valve implantation, preferably via the femoral route. The outcomes of this procedure are better in women than in men despite a more frequent occurrence of vascular, bleeding and cerebral complications. Several hypotheses have been reported in the literature regarding the reasons for such differences. Among other reasons, it is likely that in female patients, the myocardium adjusts better to the occurrence of aortic stenosis and that recovery after valve treatment is also more optimal. Another explanation is the higher frequency of coronary artery disease in this older population. This has a considerable impact on the outcome even when coronary lesions are treated prior to valve implantation. There is still room for improvement and progress can be achieved by further reducing the size of the equipment used in order to decrease the diameter of the vascular access, and by continuing to simplify TAVI procedures. Less invasive techniques should result in decreased complication rates. In addition, dedicated studies should allow us to further improve our practice in this growing population of vulnerable patients.

[Transfemoral TAVI procedure in women: Minimally-invasive technique]. / Procédure de TAVI par voie fémorale chez la femme : technique minimaliste.

Demographic data point to a substantial proportion of women in the population of elderly patients with an increasing prevalence of aortic stenosis. Implantation of an aortic bioprosthesis via an endovascular approach known as Transcatheter aortic valve implantation (TAVI) in patients presenting with a symptomatic tight aortic stenosis (severe aortic stenosis) (AS) is an alternative therapeutic option to surgical aortic valve replacement in patients at high surgical risk or ineligible for surgery. The literature has shown that this technique seems to be particularly beneficial in female patients. In the Partner A trial, the 1-year mortality rate was significantly lower in women compared to their male counterparts. Other data revealed that although women have a higher risk of experiencing periprocedural complications (vascular events, bleeding and stroke), their outcome is good and often better than that of men. These results are continuously improving thanks to the enhancement of techniques and devices. In view of the published reports reflecting the increasing experience of the teams, it clearly appears that the simplification of TAVI procedures has resulted in improved outcomes. We report here the case of a patient treated by means of a "minimalist" approach to TAVI allowing a reduction of the risks inherent in the procedure. This simplified strategy relies on an optimal use of CT scan findings prior to TAVI. The procedure is carried out under local anesthesia and the main access site is sutured percutaneously (Proglides). The radial artery is used as a secondary access site. Contrast medium is diluted and stimulation is administered via the intraventricular guidewire. Direct stenting is performed when deemed feasible on the basis of CT scan results. Simplified procedures such as these contribute to the improvement of TAVI outcomes. However, further studies focusing on female patients are warranted in order to corroborate these findings.

[Renal denervation by trans-radial access for resistant hypertension]. / Dénervation rénale par voie radiale pour le traitement d'une hypertension artérielle résistante.

Renal denervation which consists in the ablation of the sympathetic fibers located in the adventitia of renal arteries is a therapeutic strategy allowing improved arterial hypertension control in patients who do not respond to medical treatment. This technique is currently performed using the femoral approach in the majority of cases. The diameter and the length of the ablation catheters limit their use via the radial route. The most frequent peri-procedural complications are vascular problems. We report here two cases of renal denervation via the trans-humeral and trans-radial routes respectively.

[Renal denervation a treatment for resistant hypertension: a French experience]. / La dénervation rénale un traitement pour l'hypertension artérielle résistante : expérience française.

Arterial hypertension is the largest single contributor to global mortality, and is poorly controlled in approximately 50% of patients despite lifestyle and pharmacologic interventions. Randomized clinical trials have demonstrated that catheter-based renal sympathetic denervation reduces blood pressure (BP) in patients with resistant hypertension. We sought to evaluate the efficacy of this novel therapy in "Real World" clinical practice. Consecutive patients with treatment-resistant primary hypertension, as defined as home BP>160 mmHg despite treatment with ≥3 antihypertensive drugs, were selected for denervation following renal artery screening. Ambulatory and home BP monitoring was performed in all patients prior to and following percutaneous renal sympathetic denervation. In total, 35 patients were selected for catheter-based renal sympathetic denervation. The mean age was 63.6 ± 11.7 years, 37.1% were women, 37.1% were diabetic, and 11.4% had renal impairment (GFR<45 mL/min). The basal BP (home or ambulatory) was 179.1 ± 20.75/99.66 ± 19.76 mmHg, despite an average of 4.91 ± 0.98 medications per patient. Successful bilateral sympathetic denervation was performed in 33/35 patients (1 renal artery stenosis on angiography [not ablated], 1 patient with renal artery spasm [unilateral denervation]), with an average 5.9 ± 1.6 ablations per renal artery. No procedural complications occurred. At 6 months, blood pressure was 15.5 ± 22.37/87.76 ± 13.97 mmHg (P<0.01). At 2 years follow-up, systolic blood pressure (ABPM or Home BP) was 143.8 ± 15.30 mmHg (P<0.0001) and diastolic 83.42 ± 12.80 mmHg (P=0.0004). There were no adverse events during follow-up, and no deterioration in renal function was observed. Catheter-based renal denervation is safe and efficacious treatment, which results in significant reductions in blood pressure in patients with treatment-resistant hypertension, stable at 2 years follow-up. These results are applicable to real-world patient populations.

[Renal artery denervation for treating refractory hypertension]. / La dénervation rénale un traitement pour l'hypertension artérielle résistante.

Arterial hypertension is a major healthcare issue affecting between 30 and 40% of the adult population in industrialized countries. Despite the availability of numerous pharmaceutical treatments, arterial hypertension often remains uncontrolled. A non-negligible percentage of patients are refractory to multiple-drug therapy, which exposes them to an increased risk of cardiovascular events. Percutaneous, renal denervation using a catheter connected to a low energy radiofrequency generator has proven effective in decreasing arterial pressure in patients resistant to medical therapy, by reducing afferent nerve activity. In order to be eligible for this therapeutic approach, patients must have uncontrolled essential hypertension despite treatment with a combination of three anti-hypertensive drugs including a diuretic agent, and ≥ 45mL/min glomerular filtration rate. The initial registry study demonstrated that catheter-based sympathetic renal denervation was a simple and safe procedure resulting in a significant and durable reduction in arterial pressure. Subsequently, a randomized controlled trial (the Symplicity HTN-2 trial) showed a mean 32/12 mmHg decrease in blood pressure measurements in the group of patients who underwent renal denervation whereas no difference was observed in the control group. The reduction in blood pressure was still present at 24-month follow-up. No procedure-related complications were reported and no instances of renal artery stenosis or aneurysmal dilatation were evidenced during the follow-up period. No cases of renal function impairment or deterioration were recorded. This technique seems to be a promising strategy in patients suffering from this serious condition. In order to demonstrate the actual benefit of this technique, we report the case of two patients who underwent renal denervation in our institution.

[Electromechanical mapping of myocardial ischemia in coronary occlusion in the pig]. / Cartographie électromécanique du myocarde ischémique dans un modèle d'occlusion coronaire progressive chez le porc.

The NOGA-Biosense catheter-based mapping technique has been well studied experimentally in infarction model. However, chronic myocardial ischemia with this new device has not been well explored. Thus, the aim of our study was to assess electromechanical changes in a pig aneroid constricor model. To achieved this aim, ten pigs were studied 21 days after the implantation of an aneroid constrictor around the circumflex artery. Coronary reserve assess by intracoronary Doppler flow wire was reduced in the ischemic lateral area (ILA) compared with the nonischemic zone (NIZ) (1.3 +/- 0.1 in the ILA vs. 2.3 +/- 0.2 in the NSZ; p < 0.01). TM echocardiography was used to evaluate myocardial regional contractility under basal condition and after stress induced by rapid atrial pacing. In stress state, the ischemic zone showed an impaired contractility compared with basal state (wall thickening, 32.7 +/- 7.4% vs. 59.7 +/- 8.6%; p < 0.05) whereas the non ischemic zone did not (53.8 +/- 7.6% vs. 60.8 +/- 10.1%; p = ns). Constrast echography showed a decrease in contrast intensity in subendocardium of the ila compared with the niz (46.2 +/- 16.6 vs. 99.2 +/- 35.6; p = 0.03) in pacing. Ventricular mapping quantified unipolar (UV). bipolar (BV) voltage potentials and endocardial local shortening (LLS) in 9 left ventricular regions. In basal state, electrical potentials were preserved in both zones (UV: 9.1 +/- 1.8 mV in the ischemic vs 11.3 +/- 3.6 mV in the non ischemic zone; p = ns; BV: 4.2 +/- 1.1 mV in the ILA vs. 3.9 +/- 1.5 mV; p = ns). In contrast, LLS was significantly lower in the ischemic compared with non ischemic zone (6.4 +/- 5.4% vs. 17.9 +/- 3.0%, p < 0.001). In conclusion, ventricular mapping with the NOGA-Biosense system can identify the ischemic myocardium. In this pig model, the association of a preserved electrical activity and an impaired mechanical activity characterizes the ischemic myocardium. These findings could be interesting in this model in regard of the new developments of the system in particular in the field of angiogenesis.

[Angioplasty of a right coronary artery arising from a single coronary artery during acute myocardial infarction]. / Angioplastie d'une artère coronaire droite issue d'un tronc commun unique à la phase évolutive d'un infarctus du myocarde.

The authors report the case of a patient admitted for acute inferior myocardial infarction with right ventricular extension secondary to occlusion of the right coronary artery arising from a single coronary artery treated by angioplasty and stenting by a right radial approach after treatment with Abxicimab.