Assessment of valve implantation in the descending aorta as an alternative for aortic regurgitation patients not treatable with conventional procedures

BACKGROUND

Aortic Regurgitation (AR) produces the entrance of an abnormal amount of blood in the left ventricle. This disease is responsible for high morbidity and mortality worldwide and may be caused by an aortic valve dysfunction. Surgical and transcatheter aortic valve replacement (TAVR) are the current options for treating AR. They have replaced older procedures such as Hufnagel's one. However, some physicians have reconsidered this procedure as a less aggressive alternative for patients not eligible for surgical or TAVR. Although Hufnagel suggested a 75% regurgitation reduction when a valve is placed in the descending aorta, a quantification of this value has not been reported.

METHODS

In this paper, CFD/FSI numerical simulation is conducted on an idealized geometry. We quantify the effect of placing a bileaflet mechanical heart valve in the descending aorta on a moderate-severe AR case. A three-element Windkessel model is employed to prescribe pressure outlet boundary conditions. We calculate the resulting flow rates and pressures at the aorta and first-generation vessels. Moreover, we evaluate several indices to assess the improvement due to the valve introduction.

RESULTS AND CONCLUSIONS

Regurgitation fraction (RF) is reduced from 37.5% (without valve) to 18.0% (with valve) in a single cardiac cycle. This reduction clearly shows the remarkable efficacy of the rescued technique. It will further ameliorate the left ventricle function in the long-term. Moreover, the calculations show that the implantation in that location introduces fewer incompatibilities' risks than a conventional one. The proposed methodology can be extended to any particular conditions (pressure waveforms/geometry) and is designed to assess usual clinical parameters employed by physicians.

Temporal trend and potential impact of angiotensin receptor neprilysin inhibitors on transcatheter edge-to-edge mitral valve repair

INTRODUCTION AND OBJECTIVES

Transcatheter edge-to-edge repair (TEER) should be considered in patients with heart failure and secondary mitral regurgitation (MR). Angiotensin receptor-neprilysin inhibitors (ARNIs) have been demonstrated to improve prognosis in heart failure. We aimed to evaluate the impact ARNIs on patient selection and outcomes.

METHODS

The population of the Spanish TEER prospective registry (March 2012 to January 2021) was divided into 2 groups: a) TEER before the ARNI era (n=450) and b) TEER after the recommendation of ARNIs by European Guidelines (n=639), with further analysis according to intake (n=52) or not (n=587) of ARNIs.

RESULTS

A total of 1089 consecutive patients underwent TEER for secondary MR. In the ARNI era, there was a reduction in left ventricle dilation (82mL vs 100mL, P=.025), and better function (35% vs 38%, P=.011). At 2 years of follow-up, mortality (10.6% vs 17.3%, P <.001) and heart failure readmissions (16.6% vs 27.8%, P <.001) were lower in the ARNI era, but not recurrent MR. In the ARNI era, 1- and 2-year mortality were similar irrespective of ARNI intake but patients on ARNIs had a lower risk of readmission+mortality at 2 years (OR, 0.369; 95%CI, 0.137-0.992; P=.048), better NYHA class, and lower recurrence of MR III-IV (1.9% vs 14.3%, P=.011).

CONCLUSIONS

Better patient selection for TEER has been achieved in the last few years with a parallel improvement in outcomes. The use of ARNIs was associated with a significant reduction in overall events, better NYHA class, and lower MR recurrence.

A comprehensive comparison of various patient-specific CFD models of the left atrium for atrial fibrillation patients

BACKGROUND

Recently, advances in medical imaging, segmentation techniques, and high-performance computing have supported the use of patient-specific computational fluid dynamics (CFD) simulations. At present, CFD-compatible atrium geometries can be easily reconstructed from atrium images, providing important insight into the atrial fibrillation (AF) phenomenon, and assistance during therapy selection and surgical procedures. However, the hypothesis assumed for such CFD models should be adequately validated.

AIM

This work aims to perform an extensive study of the different hypotheses that are commonly assumed when performing atrial simulations for AF patients, as well as to evaluate and compare the range of indices that are usually applied to assess thrombus formation within the left atrium appendage (LAA).

METHODS

The atrial geometries of two AF patients have been segmented. The resulting geometries have been registered and interpolated to construct a dynamic mesh, which has been employed to compare the rigid and flexible models. Two families of hemodynamic indices have been calculated and compared: wall shear-based and blood age distribution-based.

RESULTS

The findings of this study illustrate the importance of validating the rigid atrium hypothesis when utilizing an AF CFD model. In particular, the absence of the A-wave contraction does not avoid a certain degree of passive atrial contraction, making the rigid model a poor approximation in some cases. Moreover, a new thrombosis predicting index has been proposed, i.e., M4, which has been shown to predict stasis more effectively than other indicators.

Optimisation of imaging protocols in interventional cardiology: impact on patient doses

The purpose of this work is to evaluate the impact of the imaging protocol as part of the optimisation of patient doses in interventional cardiology. This paper reports the results of an initial study to refine the existing fluoroscopy and cine settings, evaluates a new imaging protocol by measuring the image quality and phantom entrance air kerma values, and tests the clinical implementation of the new protocol in terms of the reduction in patient doses and the impact on clinical images. The initial study developed a new fluoroscopy mode using 7.5 frames s^-1 (instead of the previous 15 frames s^-1) with a similar dose/frame and a reduction of approximately 26% in dose/frame for the existing standard cine mode. For the new imaging protocol, the reduction in entrance air kerma was characterised for water depths of 16, 20, and 24 cm and the image quality was evaluated using a Leeds test object. A reduction in dose of around 50% was observed for the low fluoroscopy mode and an 18%-38% reduction was measured for cine. The image quality was unchanged in fluoroscopy mode and did not suffer noticeable alterations in cine mode. In the clinical implementation, cardiologists evaluated the new imaging protocol in clinical practice and cooperated with medical physicists to ensure full optimisation. The image quality criteria evaluated the ability to visualise the standard coronary arteries and small vessels (<2 mm), and the proper visualisation of the heart and diaphragm. A total of 1635 interventional cardiac procedures were assessed. The median kerma-area product exhibited a reduction of 37% for CA and 43% for PTCA examinations, and the quality of the clinical images was considered sufficient for standard clinical practice.

Occupational dose reduction in cardiac catheterisation laboratory: a randomised trial using a shield drape placed on the patient

The aim of this study was to evaluate the occupational radiation dose in interventional cardiology by using a shielding drape on the patient. A random study with and without the protective material was conducted. The following control parameters were registered: demographic data, number of stents, contrast media volume, fluoroscopy time, number of cine images, kerma-area product and cumulative air kerma. Occupational dose data were obtained by electronic active dosemeters. No statistically significant differences in the analysed control parameters were registered. The median dose value received by the interventional cardiologist was 50% lower in the group with a shielding drape with a statistically significant p-value <0.001. In addition, the median value of the maximum scatter radiation dose was 31% lower in this group with a statistically significant p-value <0.001. This study showed that a shielding drape is a useful tool for reducing the occupational radiation dose in a cardiac catheterisation laboratory.

Quality Markers in Cardiology. Main Markers to Measure Quality of Results (Outcomes) and Quality Measures Related to Better Results in Clinical Practice (Performance Metrics). INCARDIO (Indicadores de Calidad en Unidades Asistenciales del Área del Corazón): A SEC/SECTCV Consensus Position Paper

Cardiology practice requires complex organization that impacts overall outcomes and may differ substantially among hospitals and communities. The aim of this consensus document is to define quality markers in cardiology, including markers to measure the quality of results (outcomes metrics) and quality measures related to better results in clinical practice (performance metrics). The document is mainly intended for the Spanish health care system and may serve as a basis for similar documents in other countries.

Reduction of occupational radiation dose in staff at the cardiac catheterisation laboratory by protective material placed on the patient

Reducing occupational radiation dose in cardiac catheterisation laboratories is one of the objectives of the radiation protection system because the procedures performed involve high levels of radiation compared with others in health care. Recommendations on protection methods used are referred to different structural types and personal protection tools. In this work, the effectiveness of a shielding drape above the patient in different geometric shapes for a standard procedure in interventional cardiology was evaluated. Values of personal dose equivalent Hp(10) obtained simultaneously with three active electronic semiconductor dosemeters located at the usual position of staff and at the C-arm have been used to show the usefulness of the shielding drape.

Comparison of imaging techniques to assess appendage anatomy and measurements for left atrial appendage closure device selection

BACKGROUND

The adequate device size selection for left atrial appendage closure is crucial to ensuring adequate implantation and for avoiding the need for multiple attempts that increase the risk of complications. Our aim was to evaluate the information obtained using different imaging techniques to select the size of the closure device in a clinical environment.

METHODS

Thirty-seven patients who consecutively underwent implantation of Amplatzer cardiac plug (ACP) devices were studied. All patients were examined using computed tomography (CT) prior to intervention. Measurements were compared to those obtained using intraoperative transesophageal echocardiography (IOTEE) and angiography. Size was determined by the longest axis of the appendage ostium. The influence of all techniques on the correct selection of final size was assessed.

RESULTS

The measurements taken using the three techniques agreed in only 21.6% of the cases, leading to accurate selection of device size. Two techniques coincided as follows: IOTEE-CT in 45.9%, angiography-CT in 35.13%, and angiography-IOTEE in 24.3%. Measurements using CT were definitive for ACP selection in 75.7% of cases, angiography in 48.6%, and echocardiography in 51.4%. Device size was undermeasured with angiography in 35.1% of cases, and with IOTEE in 24.3%; CT overmeasured 21.6% of cases. The combination of angiography-CT was the most accurate for selection of device size.

CONCLUSION

CT most often predicts the appropriate device size. If it fails, it usually overestimates the size. Agreement of measurements with all three techniques is the most accurate situation; when two agree, the most accurate combination is angiography and CT.

MGuard® stent retrieval after failed implantation and withdrawal

SUMMARY

We present two cases of right coronary artery occlusion in which MGuard® stent implantation failed for different causes, leading to a retrieval procedure adapted to the situation. Complete retrieval was possible in both cases. These cases illustrate the need for careful selection of the lesions that are going to be treated with this type of stent, for which pre-dilatation is recommended in severe lesions located just after an acute vessel angle, the evaluation of proximal angulation and calcification, as well as strategies for complete retrieval in case of implantation failure.

Triggers and anatomical substrates in the genesis and perpetuation of atrial fibrillation

The definition of atrial fibrillation (AF) as a functional electrical disorder does not reflect the significant underlying structural abnormalities. Atrial and Pulmonary Vein (PV) muscle sleeve microstructural remodeling is present, and establishes a vulnerable substrate for AF maintenance. In spite of an incomplete understanding of the anatomo-functional basis for AF, current evidence demonstrates that this arrhythmia usually requires a trigger for initiation and a vulnerable electrophysiological and/or anatomical substrate for maintenance. It is still unclear whether the trigger mechanisms include focal enhanced automaticity, triggered activity and/or micro re-entry from myocardial tissue. Initiation of AF can be favored by both parasympathetic and sympathetic stimulation, which also seem to play a role in maintaining AF. Finally, evolving clinical evidence demonstrates that inflammation is associated with new-onset and recurrent AF through a mechanism that possibly involves cellular degeneration, apoptosis, and subsequent atrial fibrosis.

Standardized review of atrial anatomy for cardiac electrophysiologists

Catheter ablation of cardiac arrhythmias has rapidly evolved from a highly experimental procedure to a standard form of therapy for various tachyarrhythmias. The advances in this field have included, first, the development of techniques of catheter ablation that often requires the precise destruction of minute amounts of arrhythmogenic tissues and, second, techniques of resynchronization therapy that require pacing different parts of the ventricles. A detailed prepocedural knowledge of cardiac anatomy can improve the safety of the procedure and its rate success. It helps the electrophysiologist to choose the appropiate region for ablation, shortening the procedural time. The atrial anatomy structures are usually localized before ablation by different imaging techniques such as fluoroscopy, electroanatomic mapping, intracardiac echocardiography or multidetector computed tomography. In this review, we describe the normal anatomy of the atria, highlighting the landmarks of interest to intervencional cardiologist, stressing their relationship to other structures. This article is part of a JCTR special issue on Cardiac Anatomy.

[Endovascular treatment of long-term complications following surgical repair of aortic coarctation]

Surgical treatment of aortic coarctation has a high success rate. However, irrespective of the surgical technique used, a significant percentage of patients develop late complications affecting the aortic wall. Reoperation to repair these complications is a complex procedure and is associated with high mortality. Recently an endovascular approach has been proposed as a promising alternative for managing these patients. Here we report a series of four patients, three of whom had an aortic aneurysm, while one had recoarctation several years after undergoing aortic coarctation surgery. All successfully underwent endovascular treatment, without complications. We describe our experience with this complex procedure and discuss a number of associated technical considerations, including vascular access, occlusion of the supraaortic arteries, and the use of intravascular ultrasound.

[Acute myocardial infarction secondary to anaphylactic reaction following shellfish ingestion. The need for rescue coronary angioplasty]

During anaphylactic (or anaphylactoid) reactions severe cardiovascular events may occur, acute myocardial infarction among them. This etiology of myocardial infarction, is known, although it is infrequent and only sporadically reported in literature. A case of acute myocardial infarction secondary to anaphylactic reaction following shellfish ingestion, treated with subcutaneous epinephrine and in whom a rescue coronary angioplasty was necessary is reported. The mechanism of coronary occlusion in this kind of reaction and the possible influence on the efficacy of treatment is discussed.

[Atrial fibrillation and the Wolff-Parkinson_White syndrome in a 68-year-old patient with tuberous sclerosis]

Tuberous sclerosis is an autosomal-dominant disease with involvement of several organs, the heart included. The cardiac anomaly most frequently found is the rhabdomyoma association. However, WPW association has also been encountered more common than usual. In the majority of the published related-series, infant or adolescent patients are described. We report the case of a 68-year-old patient with tuberous sclerosis whose first cardiac manifestation was a pre-excited atrial fibrillation. This association is reviewed and the consideration of accessory pathways is highlighted as the first mechanism to take into account when arrhythmias are present in these patients even in adult age.

[Ventricular tachycardia in a patient with mid-ventricular hypertrophic myocardiopathy and apical aneurysm]

A case is presented of a 77-year-old patient who was admitted with a pattern of sustained ventricular tachycardia and diagnosed with midventricular hypertrophic myocardiopathy with apycal aneurysm. Under treatment with amiodarone at low doses, the patient is asymptomatic with no recurrence of the arrhytmias at one year. The association of midventricular hypertrophic myocardiopathy with apycal aneurysm and of those with sustained ventricular tachycardia are reviewed in conjunction with their treatment.

[Aortic intramural hematoma. An atypical pattern equivalent to aortic dissection]

A case is presented of a hypertensive woman who had suffered a stabbing back pain for some three hours, with mild irradiation to precordium and accompanied by vegetative signs. A sinusal rhythm and negative T waves of little depth were seen on the ECG. A transthoracic bidimensional echocardiogram (TTE) showed a normal left ventricle with a somewhat dilated aortic root and the existence of a double echo running parallel to the anterior wall of the aorta but non-ondulating and without a visible intimal flap. Because of suspected aortic dissection an urgent contrasted CAT and a transesophageal echocardiogram were performed. These were informed as an aneurysm of the aortic root with mural thrombus from the ascending to descending aorta, but with no existing intimal flap suggesting dissection. A cardiac catheterization showed a mildly some dilated aortic root without dissection signs and normal left ventricle and coronary arteries. The patient was presented for surgical evaluation but, since no dissection was present, was not considered urgent surgery; she was admitted to the coronary unit and died 48 hours later in a situation of acute pericardial tamponade, documented by TTE, surely due to rupture of the aortic root to pericardial sack. This way of presenting threatened aorta rupture that has been only recently recognized is discussed, as well as some misconceptions which must be avoided.

[Conventional stress test in patients with dilated cardiomyopathy. Variables with prognostic value. Correlations with non-invasive and invasive tests]

The variables of conventional stress testing were studied to determine their prognostic value and their correlations with other tests, in 34 patients with dilated cardiomyopathy divided into a first group of 20 in-patients admitted because of acute pulmonary edema (GI), and a second group of 14 stable out-patients (GII), with a mean follow-up of 3 years. The GI-patients had data of more evolved disease as reflected by a lower fractional shortening (13.5 +/- 4.6 vs 17.8 +/- 3.9%; p < 0.05). The only variables with prognostic capacity were functional aerobic incapacity (FAI), and systolic arterial pressure reached on exercise (SAPE), this being applicable only to GI-patients (FAI: 19.6 +/- 17.34 vs 46 +/- 26.4% in alive vs patients who died respectively; p < 0.05) (SAPE: 155 +/- 23.21 vs 127.14 +/- 24.9 mmHg, respectively; p < 0.05). Also a good correlation between the cardiac rate reached on exercise and the cardiothoracic index on chest X-ray was found (p = 0.0001), again, for GI-patients only. The presence of ventricular arrhythmias (VA) on stress testing had a very good correlation with a Holter VA-score (p < 0.0001), this being applicable for both GI and GII patients. The correlations with haemodynamic variables obtained by, basal or post-dobutamine infusion, right catheterism were not good by and large, except between FAI and systemic resistances. It is conclude that: 1) Conventional stress testing provides variables of prognostic value in dilated cardiomyopathy patients but only in those with more evolved disease. These variables are the FAI and the SAPE. 2) The presence of VA during exercise predicts their presence in daily life, and in this case at an earlier phase of the disease. 3) There are not good correlations between the haemodynamic and stress testing variables except in the case of systemic resistances and FAI.