Cardiac Venous Research Articles

Orthodromic and Antidromic Snare Techniques for Left Ventricular Lead Implantation in Cardiac Resynchronization Therapy

The snare technique can be used to overcome unsuitable cardiac venous anatomies for left ventricular (LV) lead implantation in cardiac resynchronization therapy (CRT) procedures. However, limited data exist regarding performance of the snare technique. We classified 262 patients undergoing CRT procedure into the snare (n = 20) or conventional group (n = 242) according to the LV lead implantation method. We compared the safety, efficacy, and composite outcome (all-cause death and heart failure readmission) at 3 years post-implant between the snare and conventional groups. In the snare group, all LV leads were implanted safely using orthodromic (n = 15) or antidromic (n = 5) techniques, and no immediate complications occurred including vessel perforation, tamponade, and lead dislodgement. During follow-up, LV lead threshold and impedance remained stable without requiring lead revision in the snare group. There were no significant between-group differences regarding LV ejection fraction increase (12 ± 13% vs. 12 ± 13%, p = 0.929) and LV end-systolic volume reduction (18 ± 48% vs. 28 ± 31%, p = 0.501). Both groups exhibited comparable CRT-response rates (62.5% vs. 60.6%, p = 1.000). The risk of primary outcome was not significantly different between the two groups (25.9% vs. 30.9%, p = 0.817). In patients who failed conventional LV lead implantation for CRT, the snare technique could be a safe and effective solution to overcome difficult coronary venous anatomy.

Fsp1 cardiac embryonic expression delineates atrioventricular endocardial cushion, coronary venous and lymphatic valve development.

Fsp1 (a.k.a S100A4 or Metastatin) is an intracellular and secreted protein widely regarded as a fibroblast marker. Recent studies have nonetheless shown that Fsp1 is also expressed by other cell types, including small subsets of endothelial cells. Since no detailed and systematic description of Fsp1 spatio-temporal expression pattern in cardiac vascular cells is available in the literature, we have used a transgenic murine line (Fsp1-GFP) to study Fsp1 expression in the developing and postnatal cardiac vasculature and endocardium. Our work shows that Fsp1 is expressed in the endocardium and mesenchyme of atrioventricular valve primordia, as well as in some coronary venous and lymphatic endothelial cells. Fsp1 expression in cardiac venous and lymphatic endothelium is progressively restricted to the leaflets of cardiac venous and lymphatic valves. Our results suggest that Fsp1 could play a role in the development of atrioventricular valves and participate in the patterning and morphogenesis of cardiac venous and lymphatic vessel valves.

Coronary sinus diverticulum: Importance, function, and treatment.

The importance of venous structure in the heart is usually overshadowed by that of the arterial system. Coronary sinus (CS) is a part of cardiac venous apparatus and connects left atria to the right atria. Other than having role in physiological contractions of both atria, it contributes substantially to cardiac electrical conduction system. Due to unique placement and connections of the CS, it has become growing interest in clinical cardiology. It is used in cardiac resynchronization therapy with biventricular pacing, left-sided catheter ablation of arrhythmias, and administration of retrograde cardioplegia in cardiac surgery. In some individuals, CS is presented with anatomical variants. CS diverticulum is a congenital outpouching that provides muscular connection between atria and ventricle. This connection provides a suitable substrate for occurrence of arrhythmias, which even results in life-threatening events such as sudden cardiac death. Early diagnosis leads to treatment with ablation techniques, which ultimately eliminates origins of arrhythmias.

Absence of Pre-Transplant Pulmonary Features of Sarcoidosis is of Low Negative Predictive Value in End-Stage Cardiac Sarcoidosis

Purpose Cardiac sarcoidosis is a potentially reversible etiology of heart failure if identified and managed in a timely fashion. Given the multisystem nature of the disease and need for a high index of suspicion, diagnosis of cardiac sarcoidosis is difficult, and the underlying cause remains speculative. Methods In a single-center retrospective case-control study of 15 patients with pathologic evidence of cardiac sarcoidosis that required cardiac transplantation or left ventricular assist device placement, diagnosed by diagnostic granulomas on native heart cardiectomy or apical core, and 33 matched controls, we collected pre-transplant pulmonary function testing (PFT) and right heart catheterization (RHC) data. We performed a blinded review of pre-transplant chest CT to categorize each scan as likely, possible, or unlikely for sarcoidosis. Results Mean age in the cardiac sarcoidosis group was 59 years and 67% were male. The FVC, FEV1, TLC, and DLCO were similar in both groups. RHC showed comparable hemodynamics with a non-significant trend towards lower cardiac index and lower mixed venous O2 saturation in the sarcoidosis group. Figure 1 shows the distribution of chest CT interpretation. Sensitivity and specificity of the chest CT classification in predicting cardiac sarcoidosis were 0.79 and 0.38, respectively, with positive predictive value of 0.41 (95%CI, 0.22-0.61) and negative predictive value of 0.77 (0.46-0.95). Conclusion PFT and RHC data did not independently differentiate the likelihood of cardiac sarcoidosis in our sample. Chest CT scans may identify patients with nonischemic heart failure who need to be considered for workup of cardiac sarcoidosis. However, absence of clear pulmonary radiographic or PFT finding at the time of tertiary referral did not exclude the diagnosis. It remains unclear whether sarcoidosis with end-stage physiology limited to the heart represents a distinct pathological entity from pulmonary-predominant sarcoidosis.

First in man prolonged pressure-controlled intermittent coronary sinus occlusion to treat refractory left ventricular dysfunction and ischemia with patent epicardial coronary arteries

AimsPressure-controlled Intermittent Coronary Sinus Occlusion (PICSO) intermittently increases the pressure in the cardiac venous outflow tract using a balloon-tipped catheter introduced percutaneously into the coronary sinus. It aims to improve microvascular perfusion in STEMI patients during PCI, thus improving infarct healing. Its successful administration was associated with an improvement in myocardial recovery four months after primary-PCI as compared to control. However, it has never been used in other settings or for a prolonged period.The aim of this study was to report on the feasibility and efficacy of prolonged PICSO to treat refractory LV dysfunction and ischemia. Methods and resultsTwo patients with refractory LV dysfunction and ongoing ischemia with patent epicardial coronary artery and suspected underlying microvascular dysfunction were treated with prolonged off-label PICSO utilization. A medium of 23,990mmHg PICSO quantity (a marker of PICSO therapy performance) was achieved: it was almost fifty times the PICSO quantity previously reported in in short-term PICSO utilization. After PICSO placement, both patients showed significant improvement of myocardial ischemia and recovery of LV systolic function. ConclusionProlonged PICSO utilization was feasible and effective in two patients. These cases highlight a novel application of PICSO technology: redistribution of venous blood and improvement in microvascular perfusion that might be a new target in cases of refractory LV dysfunction and ongoing ischemia in the setting of patent epicardial coronary arteries.

Anatomic Thoracoscopic Repair of Esophageal Atresia.

The thoracoscopic approach to repair esophageal atresia (EA) with tracheoesophageal fistula (TEF) provides excellent view, allowing the most skillful surgeons to spare the azygos vein by performing the esophageal anastomosis over (on the right side) the azygos vein. Seeking the most anatomic repair, we started to perform the esophageal anastomosis underneath (on the left side) the azygos vein: anatomic thoracoscopic repair of esophageal atresia (ATREA). We aim to compare results of ATREA with the classic thoracoscopic repair. During the last 4 years, in our center, all infants with EA with distal TEF were operated by thoracoscopy sparing the azygos vein. According to the surgical technique, two groups were created: Group A-treated with ATREA and Group B-treated with classic thoracoscopic repair over (on the right side) the azygos vein. We retrospectively collected data regarding features of the newborn (gestational age, gender, karyotype changes, associated anomalies, birth weight), surgery (operative technique, operative time, and surgical complications), hospitalization (duration of mechanical ventilation, thoracic drainage, time for the first feeding, time of admission, and early complications) and follow-up [tracheomalacia, gastroesophageal reflux disease (GERD), anastomotic stricture, recurrence of fistula]. Group A had seven newborns and Group B had four newborns. There were no statistically significant differences between both groups concerning the evaluated variables on surgery, hospitalization, and follow-up. Nevertheless, in Group A, there was an infant with a right aortic arch where ATREA was particularly useful as it avoided that the azygos vein and the aortic arch were left compressed in between the esophagus and trachea. Postoperatively, one patient of Group B had a major anastomotic leak with empyema requiring surgical re-intervention. During follow-up, anastomotic stricture requiring esophageal dilation occurred with similar rates in both groups. In Group B, one patient had severe and symptomatic tracheomalacia requiring aortopexy and severe GERD requiring fundoplication. No patients developed recurrent fistula. The ATREA is feasible in the great majority of patients with EA with TEF without compromising long-term results and might be particularly useful for those infants with malformations of the cardiac venous return vessels and/or major aortic malformations.

Coronary Sinus Anatomy and its Importance-evidence based Review

Coronary sinus is the largest cardiac venous channel and its increasingly used during electrophysiological procedures like LV pacing, biventricular ICD lead placement and ablation. There are few other novel procedures under research including stem cell delivery in case of ischemic myocardium. Coronary sinus anatomy, its variations in tributaries and the clinical implications are discussed in this review article.

A Twist of Proepicardial Fate

In the developing vertebrate heart, cells that contribute to vascular smooth muscle, cardiac fibroblasts, and coronary endothelial cells are derived from the proepicardium and associated cells originally located at the venous pole of the primitive heart tube. Recently, there has been much interest in the regulatory mechanisms that control epicardium-derived cell (EPDC) lineage development and mobilization with adult cardiac injury. However, less is known of the embryonic origins and inductive mechanisms that control the initial induction of the proepicardium. The study by Schlueter and Brand1 in the current issue of Circulation Research reports fate mapping of proepicardial progenitors to the somatic mesoderm and demonstrates a critical role for the basic helix-loop-helix transcription factor Twist1 in the earliest stages of proepicardial development. Article, see p 1128 The heart is the first organ to function in the developing vertebrate embryo, and beating of the primitive heart tube is apparent by embryonic day (E)8 in mouse and by 40 hours of development in chicken embryos.2 As the primitive heart tube loops, lateral plate mesoderm cells on the right side of the embryo at the cardiac venous pole begin to form the proepicardium.3 Schlueter and Brand1 demonstrate through fate mapping studies in avian embryos that at least some cells of the proepicardium are derived from the somatic layer of lateral plate mesoderm. The somatic compartment (somatopleure) of the lateral plate mesoderm is adjacent to the ectoderm and forms the body wall.4 The new data provide initial evidence that cells of the proepicardium also are derived from somatic mesodermal layer. The proepicardium shares many characteristics with other mesothelia of the major coelomic organs that contribute progenitors of fibroblasts and smooth muscle to the lung, gut, kidney, etc.4 The embryonic origins of coelomic mesothelia are not …

EComment. Cardiac venous arterialization in acute myocardial infarction

We read the article by Munz et al. with interest [1]. They aimed to investigate the benefits of cardiac venous arterialization in reducing acute myocardial infarct size and its effects on cardiac performance. This study revealed that selective cardiac venous arterialization can nourish the myocardium and is able to reduce the infarct size by more than 50%, while protecting cardiac performance. The study is successfully planned and the results are presented well — thanks to the authors for their contribution. In the absence of collateral circulation, coronary occlusion causes myocyte necrosis, the extent of which correlates directly with the speed and duration of the occlusion. Early reperfusion of an ischaemia related artery (IRA) would decrease myocardial necrosis, improve left ventricular (LV) function, and reduce mortality rates. Opening an occluded IRA, whether early or late, produces survival rates disproportionate to the amount of myocardium salvaged. A current trial clearly showed that in patients diagnosed with acute coronary syndrome, an early invasive approach is superior to a conservative approach [3]. Early reintervention may limit the extent of myocardial cellular damage compared with conservative medical strategy in patients with myocardial ischaemia due to early graft failure as well as in patients with acute myocardial infarction [4]. Myocardial reperfusion has been shown to improve both short- and long-term survival in patients who have experienced an AMI. The open artery hypothesis suggests that survival after AMI depends on improved LV remodeling and healing, electrical stability, and myocardial perfusion rather than on the reduction of the infarct size (i.e., myocardial salvage) [5]. Studies showed that late patency of an IRA, as opposed to persistent occlusion, was independently associated with better 1-year survival. In a long-term follow-up study of 505 patients who underwent percutaneous transluminal coronary angioplasty for post-MI ischaemia, 22 patients with an open IRA had a lower 5-year mortality rate than patients with a closed IRA. This held true even for patients with LVEFs <0.50. Conflict of interest: none declared

Cardiac venous arterialization in acute myocardial infarction: how great is the benefit?

Cardiac venous arterialization has been proposed as an alternative approach for myocardial revascularization in ischaemic heart disease. It is based on using the cardiac venous system to transport arterial blood from a systemic artery to infarcted myocardial areas. Our goal was to evaluate its benefit in reducing acute myocardial infarct size and its effects on cardiac performance. In a group of pigs, the left internal mammary artery was anastomosed to the left anterior descending vein; this vein was ligated proximally. The left anterior descending coronary artery was also occluded. Over 5 days, several diagnostic procedures were used to characterize and measure the extent of myocardial infarct, namely ECG, echocardiography, cardiac biomarkers and histopathology. Data were compared with those from a control group of pigs, which were submitted to ligation of only the left anterior descending coronary artery. In the experimental group, echocardiography revealed that the ejection fraction and thickness of the ventricular walls remained unchanged 4 days after surgery, in contrast to the major alterations in the control group. In fact, the ejection fraction in the control group decreased by 21% (P < 0.001), with a reduction of 31% (P < 0.004) in the thickness of the interventricular septum at end systole and enlargement of the left ventricular lumen by 28% (P < 0.001). In the experimental group, the sum for ST segment shift was 50% lower (P = 0.038) and the total ventricular histological lesion size was 50% smaller (P < 0.001). Within this lesion, the area of necrotic tissue was 70% smaller (P < 0.001). Cardiac biomarkers were not different between the two groups (P > 0.2). This study reveals that selective cardiac venous arterialization can nourish the myocardium and is able to reduce infarct size by more than 50%, while protecting cardiac performance. We believe, therefore, that further investigation should be carried out into this technique in order for it to be considered as an option in coronary surgery.

Invited Commentary

Invited Commentary

Interim Results of the 5-Box Thoracoscopic Maze Procedure

In accordance with the Cox-Maze paradigm, successful treatment of atrial fibrillation (AF) requires (1) complete posterior left atrial isolation, (2) elimination of corridors for perimitral reentry, (3) elimination of cardiac venous (superior vena cava and coronary sinus) arrhythmogenic foci, (4) complete autonomic denervation, and (5) occlusion or removal of the left atrial appendage. Using a totally thoracoscopic approach, isolation of all left atrial arrhythmogenic substrate is achieved through the creation of 5 discrete but contiguous compartments, thereby enabling unambiguous verification with bidirectional block. Since no previous closed-chest procedure incorporates all these end points, an update on patient outcomes is reported. One hundred seventy-nine consecutive patients with antiarrhythmic drug-resistant AF (3 paroxysmal, 5 persistent, 171 longstanding persistent cases), known preoperatively for 5.7 (range 0.5 to 25) years, underwent the 5-box thoracoscopic Maze procedure. Only 1 patient suffered a serious procedural complication (sternotomy for pulmonary artery injury). Postoperative rhythm surveillance consisted of 1 week of continuous ambulatory monitoring at 3, 6, 13, and 24 months. Failure was defined as any tachyarrhythmia exceeding 30 seconds beyond the 3-month anniversary. Freedom from AF was observed in 137 of 142 patients at 3 months, 115 of 119 patients at 6 months, 75 of 78 patients at 13 months, and 24 of 25 patients at 24 months. Two patients remain in sinus rhythm on low-dose antiarrhythmia therapy. Warfarin is discontinued only after the first monitoring session confirms rhythm stability. Replication of the left atrial Cox-Maze lesion set through a totally thoracoscopic approach isolates virtually all arrhythmogenic substrate. Meticulous verification of compartment integrity allows for outcomes equivalent to the Cox-Maze benchmark.

Cardiac Venous Left Ventricular Lead Removal and Reimplantation Following Device Infection: A Large Single‐Center Experience

Early series of biventricular device removal have contained mostly younger cardiac venous (CV) left ventricular leads and few have reported on rates of successful reimplantation. We performed a retrospective analysis of all patients referred to the Cleveland Clinic between February 2, 2001 and July 27, 2011 for removal of a biventricular device with a CV pacing lead for an infectious indication. A total of 173 patients were included. The median age of the CV leads was 22.3 months (interquartile range: 5.2-46.3 months). The complete procedural success rate for all leads was 97.7%, with the remaining 2.3% clinical successes. A total of 76.9% of CV leads were removed using simple traction alone with the remaining leads requiring the use of a laser-powered sheath. A total of 3.5% of leads required intervention (manual dissection or laser-powered dissection) within the coronary sinus (CS). Major complications occurred in 1.2% of patients. Minor complications occurred in 7.5% of patients, the majority of which were hematomas requiring drainage (6.9%). CV lead reimplantation was attempted in 107 patients of which 88 (82.8%) were successful. CV lead removal in patients with an infected biventricular device is associated with an extremely high procedural success rate and a low incidence of major complications. The use of a laser-powered sheath is necessary in roughly one-quarter of cases with a very small percentage requiring intervention within the CS. Reimplantation of CV leads is achievable in roughly 83% of patients, a figure lower than nationally quoted estimates for de novo implantations.

Imaging of the Coronary Sinus: Normal Anatomy and Congenital Abnormalities

Knowledge of the anatomy of the coronary sinus (CS) and cardiac venous drainage is important because of its relevance in electrophysiologic procedures and cardiac surgeries. Several procedures make use of the CS, such as left ventricular pacing, mapping and ablation of arrhythmias, retrograde cardioplegia, targeted drug delivery, and stem cell therapy. As a result, it is more important for physicians interpreting the results of computed tomographic (CT) examinations dedicated to the heart or including the heart to be able to identify normal variants and congenital anomalies and to understand their clinical importance. Abnormalities of the CS range from anatomic morphologic variations to hemodynamically significant anomalies such as an unroofed CS, anomalous pulmonary venous connection to the CS, and coronary artery-CS fistula. It can be important to identify some anatomic variations, even though they are clinically occult, to ensure appropriate preprocedural planning. Both CT and magnetic resonance imaging provide excellent noninvasive depiction of the anatomy and anomalies of the CS. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.324105220/-/DC1.

Hemodynamic differences between the awake and anesthetized conditions in normal calves

There is insufficient information in the literature about baseline circulatory parameters in normal calves in the anesthetized versus postoperative awake conditions under which a large volume of medical research is conducted. Eleven calves (mean body weight, 78.1±14.3kg) were implanted with a flow probe and fluid-filled pressure lines to measure cardiac output (CO), aortic (AoP), central venous (CVP), pulmonary arterial (PAP), and left atrial pressures (LAP). Systemic (SVR) and pulmonary vascular resistance (PVR) were also calculated. We obtained the above hemodynamic data (n=11) and epicardial echocardiography (n=7) during open-chest surgery under isoflurane anesthesia. After full recovery from surgery, animals were evaluated in the awake condition on postoperative days 6-9 using transthoracic echocardiography (n=7) and the hemodynamic monitoring lines and probes noted (n=11). CO, AoP, and PAP levels in the anesthetized condition were significantly lower than in the awake condition. Other hemodynamic parameters (CVP, LAP, SVR, and PVR) were not significantly different. In conclusion, data from this study quantify changes in CO, AoP, and PAP in anesthetized calves that may affect the hemodynamic response to experimental therapeutics such as new cardiac assist devices, prosthetic valves, and surgical interventions. Our study also provides baseline data for the translation of the hemodynamic data obtained in acute in vivo calf studies to that of an awake subject.

Modeling of Induced Electric Fields as a Function of Cardiac Anatomy and Venous Pacing Lead Location

The combined effects of cardiac anatomy and pacing lead electrode location within left ventricular cardiac veins on resultant pacing thresholds are not well understood. The specific aims of this study were to: (1) develop a comparative electrostatic model based on previously obtained histological measurements, and (2) compare resulting electric fields and voltage gradients with in vitro experimental results. In vitro pacing thresholds measured from swine hearts were utilized to model electric fields generated from different cardiac venous pacing locations within veins of varying diameter and fat thickness. The simulated activation fields were defined as 100 V/m and all materials were defined as isotropic. The obtained results predicted larger activation fields when an electrode was oriented away from the myocardium or in free-floating positions, hence requiring more myocardial tissue to have 100 V/m than when it was oriented toward the myocardium. Thus, the resultant modeled electric fields followed the same qualitative trends as in vitro experiments performed in the swine hearts. In general, while electrode position primarily affected pacing thresholds, both vein diameter and relative epicardial fat thickness also influenced pacing thresholds. The electric fields were larger for basal regions modeled using larger vein diameters and epicardial fat thicknesses. These electrostatic field simulations provide unique insights as to how varied cardiac anatomies and relative electrode locations affect thresholds by enabling visualization of the electric fields propagating through cardiac tissues during pacing from the venous system.

Ablation of epicardial ventricular arrhythmias from nonepicardial sites

Idiopathic epicardial ventricular arrhythmias can be targeted from the coronary venous system or the pericardial space, the endocardium, or the aortic sinus cusps. The purpose of this study was to analyze systematically the contribution of ablation at sites other than the epicardium to eliminate an arrhythmia originating in the epicardium. In a consecutive patient series of 33 patients (14 women, age 51 ± 14 years, ejection fraction 51% ± 9%) with epicardial ventricular arrhythmias, mapping and ablation was performed via the cardiac venous system/pericardial space, the aortic sinus cusp, and the left ventricular endocardium. An arrhythmia was defined as epicardial if the earliest onset of activation and a matching pace-map (≥10/12 leads) were identified in the epicardium. In 12/33 patients (36%), either an endocardial approach alone (n = 3) or a combined endocardial/epicardial (n = 6), cusp/endocardial (n = 1), or cusp/epicardial (n = 2) approach was required to eliminate the ventricular arrhythmias. In 10 of 33 patients (30%), epicardial ablation alone was effective in eliminating epicardial ventricular arrhythmias. Ablation was ineffective due to failure to reach the site of origin with the ablation catheter in 5 of 33 patients (15%), the site of origin was too close to an epicardial artery or the phrenic nerve in 3 patients (6%), and power delivery was insufficient in 3 patients (9%). About one-third of epicardial arrhythmias require ablation from sites other than the epicardium to eliminate the arrhythmia focus.

Haemodynamic and metabolic effects of timolol (Blocadren) on ischaemic myocardium.

The effects of timolol (2.5 mg i.v.) on coronary haemodynamics and myocardial metabolism were studied in 26 patients with angina pectoris. Cardiac venous flow (CVF) was measured by thermodilution technique. Blood was sampled for metabolic studies. Angina pectoris was induced by atrial pacing and the same heart rate was regained after timolol. Metabolic ischaemia was defined as reduction in myocardial lactate extraction ratio (MLE) by at least 50% and to a ratio below 0.15. The study was completed in 22 patients, 9 of whom fulfilled the metabolic criteria for ischaemia. This subgroup did not differ from the total group in any other respect than in lactate metabolism. Beta-adrenergic blockade reduced myocardial oxygen consumption (MVO2) and CVF significantly at rest, but MVO2, CVF, myocardial glucose uptake and MLE were unchanged during pacing despite a decrease in systolic aortic pressure, ejection time and reduced myocardial free fatty acid uptake. Conclusively, timolol did not reduce MVO2 and metabolic ischaemia during pacing-induced angina.

A rare mark of anomalies of cardiac venous drainage: unusual course of pacemaker lead

A rare mark of anomalies of cardiac venous drainage: unusual course of pacemaker lead

Surgical repair of coronary sinus orifice atresia with persistent left superior vena cava in heterotaxia

A 6-month-old boy was diagnosed with coronary sinus orifice atresia, double-outlet right ventricle, complete atrioventricular septal defect, pulmonary stenosis, and moderate common atrioventricular valve regurgitation associated with heterotaxy syndrome. Cardiac venous flow drained through a persistent left superior vena cava. We decided to perform coronary sinus orifice unroofing through the right atrium under a guide using a bougie. The persistent left superior vena cava was divided. Bidirectional Glenn anastomosis and edge-to-edge common atrioventricular valve repair were concomitantly performed. After a 1-year follow-up period, the patient is alive and well without any ischemic event.