Fulvio Floccari

Right ventricular diastolic function in dialysis patients could be affected by vascular access.

Tricuspid annular plane excursion (TAPSE) measurement in echocardiography is a measure of heart diastolic distensibility: a low TAPSE indicates reduced ventricular distensibility leading to diastolic dysfunction. It is a good prognostic index for cardiac mortality risk in congestive heart failure patients, adding significant prognostic information to the NYHA clinical classification. Our study was designed to evaluate the effect of a single hemodialysis (HD) session on diastolic function and TAPSE, focusing on the effects of vascular access typology. Twenty chronically uremic patients (age 51 ± 10 years, dialytic age 24 ± 8 months), without overt heart disease, underwent conventional two-dimensional and Doppler echocardiography immediately before starting and 15 min after ending a mid-week HD session. Ten patients had distal radiocephalic arterovenous fistula (AVF), and 10 had permanent central venous catheters (CVC). The amount of fluid removed by HD was 2,706 ± 1,047 g/session. HD led to a reduction in TAPSE, left ventricle end-diastole volume, left ventricle end-systole volume, right ventricle end-diastole diameter, peak early transmitral flow velocity, and the ratio of early to late Doppler velocities of diastolic mitral flow. AVF patients showed greater right ventricle diameters versus CVC patients, while TAPSE appeared higher in the latter. Only the AVF patient group showed TAPSE values <15 mm. Our data confirm the effects of terminal uremia on right ventricle function (chamber dilation, impaired diastolic function), showing that these abnormalities are more frequent in AVF patients as opposed to CVC patients. It is reasonable to explain these clinical features as the effect of preload increase operated by AVF.

Sudden cardiac death and chronic kidney disease: From pathophysiology to treatment strategies

Chronic kidney disease (CKD) patients demonstrate higher rates of cardiovascular mortality and morbidity; and increased incidence of sudden cardiac death (SCD) with declining kidney failure. Coronary artery disease (CAD) associated risk factors are the major determinants of SCD in the general population. However, current evidence suggests that in CKD patients, traditional cardiovascular risk factors may play a lesser role. Complex relationships between CKD-specific risk factors, structural heart disease, and ventricular arrhythmias (VA) contribute to the high risk of SCD. In dialysis patients, the occurrence of VA and SCD could be exacerbated by electrolyte shifts, divalent ion abnormalities, sympathetic overactivity, inflammation and iron toxicity. As outcomes in CKD patients after cardiac arrest are poor, primary and secondary prevention of SCD and cardiac arrest could reduce cardiovascular mortality in patients with CKD.

Progression of cardiac valve calcification and decline of renal function in CKD patients.

BACKGROUND No study has evaluated the efficacy of non-calcium-containing phosphate binders in slowing progression of cardiac valve calcification or deterioration of kidney function in patients with chronic kidney disease not on dialysis. This study addressed these issues. METHODS Outpatients (n = 170) with stage 3-4 chronic kidney disease and either mitral or aortic valve calcification were evaluated in this single-center, single-arm, prospective observational study. Patients received sevelamer hydrochloride (1,600 mg/day) for 1 year. Cardiac valve calcification progression was assessed by echocardiography, and decline of renal function by estimated glomerular filtration rate. Parathyroid hormone, FGF-23 and C-reactive protein (CRP) serum concentration and urinary phosphorus excretion were assayed. RESULTS At the end of treatment with sevelamer (12th month), mitral valve calcification had decreased by 79.3% from baseline. At baseline, 69 patients had grade 1, 97 patients grade 2 and 4 patients grade 3 calcification scores; at the end of the study, 60 patients showed grade 1, and no mitral valve calcification was registered in the remaining patients. An aortic valve score of 1 was found in 32%, score of 2 in 58%, score of 3 in 9% and score of 4 in 1% of patients at baseline; at the end of the study, a score of 1 was found in 95% and a score of 2 in 5% of patients. Significant slowing down of renal function decline (p<0.001), reduction of FGF-23 and CRP concentration (p<0.0001) and phosphorus excretion (p<0.0001) were observed. CONCLUSIONS One-year treatment with a non-calcium-containing phosphate binder may hamper the progression of cardiac valve calcification and slow the decline of renal function, as well as reduce serum concentration of FGF-23 and CRP and urinary phosphorus excretion.

Pulmonary Hypertension and Right Heart Failure in Chronic Kidney Disease: New Challenge for 21st-Century Cardionephrologists.

Pulmonary hypertension is defined as an increased systolic pulmonary pressure of >30 mm Hg, and it shows a 40% prevalence in hemodialysis patients due to vascular access (both central venous catheter and arteriovenous fistula). Secondary pulmonary hypertension in chronic kidney disease patients is strictly related to pulmonary circulation impairment together with chronic volume overload and increased levels of cytokines and growth factors, such as FGF, PDGF, and TGF-β, leading to fibrosis. Endothelial dysfunction, together with lower activation of NOS, increased levels of serum endothelin and fibrin storages, involves an extensive growth of endothelial cells leading to complete obliteration of pulmonary vessels. Pulmonary hypertension has no pathognomonic and distinctive symptoms and signs; standard transthoracic echocardiography allows easy assessment of compliance of the right heart chambers. The therapeutic approach is based on traditional drugs such as digitalis-derived drugs, vasodilatory agents (calcium channel blockers), and oral anticoagulants. New pharmacological agents are under investigation, such as prostaglandin analogues, endothelin receptor blockers, and phosphodiesterase-5 inhibitors.

Ultrasonography: Ariadne's Thread in the Diagnosis of the Cardiorenal Syndrome

The term cardiorenal syndrome (CRS) describes a broad spectrum of clinical conditions with four combinations of acute and chronic heart and kidney failure. Based on the pathophysiological primum movens, the actual classification recognizes five CRS types: in type I and II CRS, the initiating event is heart failure (acute or chronic), while it is kidney failure in type III and IV CRS; type V is linked to systemic diseases. Ultrasound techniques (echocardiography and ultrasonography of the kidney, inferior vena cava and chest) can be extremely helpful in establishing a prompt diagnosis and a correct CRS classification. Basic echocardiography allows evaluation of ventricular diastolic and systolic functions, investigates pulmonary congestion and pericardial effusion, and describes volume overload. On the other hand, renal ultrasound helps clinicians to distinguish between acute and chronic renal failure, excludes urinary tract dilation or pathological bladder repletion, and provides crucial information regarding kidney volume or echogenicity. Applying basic knowledge of echocardiography and renal ultrasound, nephrologists may be in a better position for patient treatment and management, bearing in mind that doctors can properly use a stethoscope although not being a cardiologist.

Penile Calciphylaxis in End Stage Renal Disease

Calciphylaxis, better described as “Calcific uremic arteriolopathy” (CUA), involves about 1–4% of hemodialysis patients all around the world with high mortality rates. We describe a rare clinical case of CUA in peritoneal dialysis patient associated with urological disease. Penile calciphylaxis represents rare clinical complication, and an early diagnosis and multidisciplinary approach are requested. Pathogenesis is still unclear, and therapeutic approaches need more long-term clinical trials to test their efficacy and safety.

A Complex Renal Cyst: It Is Time to Call the Oncologist?

Introduction. Hydatid disease is a cyclozoonotic parasitic infestation caused by the cestode Echinococcus granulosus. The cysts mainly arise in the liver (50 to 70%) or lung (20 to 30%), but any other organ can be involved, in abdominal and pelvic locations, as well as in other less common sites, which may make both diagnosis and treatment more complex. Isolated renal involvement is extremely rare. Case Presentation. We report a rare case of isolated renal hydatid disease in a 71-year-old man with a history of vague abdominal pain, anemia, fever, and microhematuria. Ultrasonographic examination revealed a complex cyst in the right kidney, including multiple smaller cysts with internal echoes. A magnetic resonance scan of the abdomen confirmed the findings, and hydatid cyst disease was diagnosed. Right nephrectomy was performed, and microscopic examination confirmed the diagnosis of hydatid cyst. Albendazole, 10 mg/kg per day, was given for 4 weeks (2 weeks preoperatively and 2 weeks postoperatively). Conclusion. Isolated primary hydatidosis of the kidney should always be considered in the differential diagnosis of any cystic renal mass, even in the absence of accompanying involvement of liver or other visceral organs.

Salvage of radiocephalic arteriovenous fistula in hemodialysis patient causing steal syndrome with endovascular coil embolization

arch, the patient was therefore scheduled for angiography with the intent to treat. Angiography was performed with the retrograde puncture of the cephalic vein. A 4 Fr introducer sheath (Terumo Medical Corporation, Tokyo, Japan) was inserted and a 4 Fr Cobra Glidecath catheter (Terumo Medical Corporation) advanced through the AVF to the BA. The angiogram shows retrograde flow through the superficial and deep palmar arch (Fig. 1A). The catheter was then placed just below the AVF in the RA before the thenar artery origin, and four pushable platinum fibered coils, 4 mm in diameter and 40 mm in length (Vortex 35; Boston Scientific Corporation), were placed with complete RA embolization below the AVF (Fig. 1B) with no postoperative complications. The patient noticed significant improvement in the symptoms. Treatments for ISS are generally limited to access ligation, DRA interruption and banding. Coil embolization of DRA in our experience was confirmed as a valid therapeutic option. We have perhaps to remind to our readers that the deployment of coils can be performed safely only when the distance between the AVF anastomosis and the thenar artery is at least 3-4 cm in the presence of an adequate UA flow. The cost of embolization procedure is approximately 600 Euros, and DRA ligation costs Dear Editor,

An unusual case of posterior nutcracker syndrome

To the Editor Nutcracker syndrome commonly refers to left renal vein compression between aorta and superior mesenteric artery, resulting in increased venous pressure, kidney congestion and proteinuria. Posterior nutcracker syndrome is a rare variant, linked to retro-aortic position of the last tract of the left renal vein which remains compressed between aorta and spinal column. We report an unusual case of posterior nutcracker syndrome in a 22-year-old man with congenital solitary left kidney who was admitted to our department because of proteinuria of 700 mg/24 h and microhematuria. Upon admission, blood pressure was 120/70 mmHg. Mild pitting edema was present in his lower limbs. Laboratory workup showed a normal renal function with a creatinine of 1.1 mg/dl. Urinalysis revealed the presence of rare hyaline and granular casts and isomorphic erythrocytes. No previous episodes of left flank pain were reported. Ultrasonography was performed showing the absence of the right kidney, compensatory hypertrophy of the left organ and dilation of the left renal vein. After a few centimeters from the hilum, the left renal vein presented an abnormal course, addressed in cranio-caudal direction until merging into inferior vena cava just below common iliac arteries (Fig. 1a). Proximal venous dilation was also noted (antero-posterior diameter 13.8 mm in the hilar area, 1.6 mm in the narrow portion, ratio 8.6). Doppler peak velocities were 25 cm/s in the hilar area and 111 cm/s in the narrow portion (ratio 4.4). An abdomen contrast-enhanced computed tomography was then carried out, confirming the anomalous course of the vein. Compression of the vein was evident between left common iliac artery and a lumbar vertebral body (Fig. 1b, c). In order to confirm the diagnosis, a right femoral vein approach was performed, and the left renal vein was visualized in a contrast-enhanced phlebography (Fig. 1d). It was dilated, with a pressure gradient of 8 mmHg versus inferior vena cava. Endovascular stenting was then carried out and a self-expandable 14–40 mm stent made of nitinole was inserted where the vein narrowed. Post-procedural phlebography documented normal flow through the vessel, with no significant pressure gradient between the left renal vein and inferior vena cava. 24-h proteinuria promptly fell below 300 mg/day. Posterior nutcracker syndrome is characterized by the abnormal retro-aortic position of the left renal vein and its subsequent compression between aorta and spinal column [1–3]. Similar to the ‘‘anterior nutcracker phenomenon’’, this syndrome usually leads to renal venous hypertension and it should be considered among the causes of recurrent left flank pain, proteinuria and hematuria. A. Granata (&) A. Clementi Nephrology and Dialysis Unit, San Giovanni Di Dio Hospital, Agrigento, Italy e-mail: antonio.granata4@tin.it

Internal jugular vein cannulation: why ultrasound guidance should be expanded as much as possible.

Internal jugular vein (IJV) is a common route of vascular access for hemodialysis. Mechanical complications during insertion are intimately related to the anatomic variations of deep central vessel relationships or to “difficult IJV” (collapsed or thrombosed vein). We performed an ultrasonographic survey of IJV on a healthy population (1,126 subjects). Each subject was asymptomatic at the time of examination. Common carotid artery (CCA) and IJV were identified on both sides of the Sedillot triangle, by anatomical criteria, compressibility of the vein, visible pulsation of the artery and pulsed Doppler examination. The following were determined: absence of IJV, collapsed IJV except during Valsalva maneuver or in Trendelenburg position, presence of partial or total IJV thrombosis (IJVT), IJV anteroposterior diameter and IJV relationship to homolateral CCA. Diagnosis of IJVT was based on vein uncompressibility, presence of intraluminal echogenic material and/or absence of phasic venous flow at Doppler examination. Exclusion criteria were history of previous central vein cannulation, neck infections, neck malignancy and pacemaker implantation. Collapsed IJV was observed in 4.6% (n=52), absence of IJV in 0.2% (n=2) and partial thrombosis in 1.3% (n=15), while only 0.9% (n=10) of subjects showed complete IJVT. The IJV was laid superficially and in the anterolateral location in 67% (n=755) on the right and 68% (n=767) on the left. A lateral position was present in 22% (n=248) on the right and 18% (n= 202) on the left. An anterior IJV was observed in 8% (n=90) on the right and 10% (n=112) on the left. The IJV was located in a miscellaneous location in 3% (n=33) on the right and 4% (n=45) on the left. Small IJV (<5 mm in diameter) was found in 12% (n=135) on the right and 17% (n=191) on the left (Tab. I).