A case of giant anastomosing hemangioma of the kidney with extramedullary hematopoiesis: A great mimicker.

Anastomosing hemangioma (AH) are rare mesenchymal neoplasms affecting kidney with about 50 cases reported in English literature. In general, they are accidentally detected during examination or imaging done for nonspecific symptoms or wellness check-up. There are no key diagnostic features on the imaging modalities. The most common preoperative diagnosis has been a malignant primary renal carcinoma. Surgical resection remains the mainstay of treatment and of choice in symptomatic lesions. We are presenting a rare case of giant AH of the kidney mimicking a renal cell carcinoma on imaging. The lesions are characterized by anastomosing sinusoidal-like vascular spaces lined by banal endothelial cells with occasional hobnail morphology and associated with extramedullary hematopoiesis. The treatment of choice could be a conservative approach in small and asymptomatic lesions and patients with pre-existing renal dysfunction; hence, this entity should be in the differential of vascular renal neoplasms considering its proclivity to the urogenital tract. This is the first case in Indian literature to the best of our knowledge.

Merkel cell carcinoma with seborrheic keratosis: A unique association.

Merkel cell carcinoma (MCC) is a rare, clinically aggressive neuroendocrine carcinoma of the skin; MCC is 40 times less common as compared to melanoma. The most frequently reported sites have been the head and neck, extremities, and trunk. Potential mimics include malignant melanoma, lymphoma, or metastatic small cell (neuroendocrine) carcinomas. Histopathology of MCC resembles small cell carcinoma both morphologically and on IHC. The possible cell of origin was proposed as the Merkel cell, which functions as a mechanoreceptor. It has a high chance of local recurrence, regional and distant spread. In recent times, Merkel cell polyomavirus has been implicated as the causative agent for this tumor. The same agent has a reported etiologic association with other skin lesions, including seborrheic keratosis.

Conventional Transbronchial Needle Aspiration: The Original Guard Who Still Has a Role in Mediastinal Lymph Node Sampling.

INTRODUCTION: Conventional transbronchial needle aspiration (C-TBNA) is the originally described method for sampling mediastinal lymph nodes (MLN). After the advent of endobronchial ultrasound, the practice and reports of C-TBNA have dwindled. We report a large series of C-TBNA from the Indian subcontinent, highlighting aspects such as pathological spectrum, yield and complications, and reiterating its relevance in MLN sampling. METHODS: The study population included 400 consecutive patients over 6.8 years who had C-TBNA done for MLN ≥1 cm in size. C-TBNA was done using a 19-G needle, with conscious sedation. A maximum of 7 passes per node were done. Rapid-on-site evaluation was done in >95% cases. Lymph nodes sampled were labeled "adequate" if lymphocytes were present, and "diagnostic" if a definitive diagnosis was made. RESULTS: The study included 228 males and 172 females, mean age 49.4±14.7 years. The "adequacy" rate was 383/400 (95.75%), and "diagnostic" yield was 347/400 (86.75%). C-TBNA was the sole diagnostic modality in 215/400 (53.75%) patients. The diagnoses included tuberculosis (43%), sarcoidosis (25.5%) and malignancy (18.25%). Complications were rare. CONCLUSIONS: This is one of the largest studies of C-TBNA in literature, and one of the few studies to define accurate pathologic diagnosis of enlarged MLN in India. This is also the one of the largest series to define the yield of TBNA with rapid-on-site evaluation in MLN sampling. Currently, in many parts of the world, C-TBNA is still the most common MLN sampling procedure, from an availability, expertise, economic, and safety perspective.

Acute hemodynamic effects of atrial pacing with cardiac resynchronization therapy.

BACKGROUND: Chronotropic incompetence is common among patients with advanced heart failure (HF), thus atrial pacing (AP) is frequently utilized in this population. The hemodynamic effects of AP during cardiac resynchronization therapy (CRT) have not been well studied. OBJECTIVE: The purpose of this study was to compare the acute hemodynamic response during CRT of AP with that during atrial sensing (AS). METHODS: This study included 26 patients undergoing CRT. At implant, invasive left ventricular (LV) dP/dt was measured by a micromanometer catheter during biventricular pacing in AS and AP modes at 5 different atrioventricluar delays (AVD), tested in randomized order. Postimplant, echocardiography was performed to obtain aortic and mitral flow velocity integrals at baseline (no CRT) and during CRT. RESULTS: Compared with intrinsic rhythm, CRT increased LV dP/dt by 11 +/- 11% during AS (heart rate: 74 +/- 13 bpm) and by 17 +/- 11% during AP (heart rate: 86 +/- 12 bpm, P < 0.001). The AVD associated with maximal hemodynamic response (AVD(max)) during AP was 72 +/- 40 ms longer than during AS. However, aortic and mitral flow velocity integrals decreased by 15-20% during AP. The aortic and mitral flow velocities at AVD(max) for LV dP/dt(max) were highly correlated with their maximum values (r > 0.98). CONCLUSION: AP increases LV dP/dt during CRT, but requires a substantially longer AV delay. However, AP results in modest reductions of LV filling and stoke volume. Further studies are needed to assess the long-term impact of AP on HF functional status and LV remodeling.

Bispectral analysis as a tool to investigate dynamics of cardiorespiratory physiology.

INTRODUCTION: Recent studies show that cardiorespiratory variables are nonlinearly coupled. In the present study, we tested the feasibility of using bispectral analysis to estimate changes in nonlinear phase coupling. METHODS: We stimulated chemo- and baro-reflexes by switching inspired gas between air and air with 5% CO2 added during supine and 70 degrees head-up tilt. Bispectra were estimated using Fourier transform of the triple cumulant and were integrated between 0.04 and 0.3 Hz. Variables analyzed included cardiac RR intervals, systolic BP (SBP), tidal volume (VT), end tidal pressure of CO2 (PETCO2) and mean cerebral blood flow velocity (CBFM). Data were collected in 30 healthy adults who were then grouped according to whether they become presyncopal (PS) during tilt or remained normal with no signs or symptoms of presyncope (NPS). RESULTS: Six subjects (20%) developed presyncope. During tilt with room air breathing, phase coupling in RR, SBP, and between RR-SBP and RR-VT was lower in PS than in NPS, while phase coupling between CBFM-SBP was higher. In contrast, during tilt with 5% inhaled CO2, phase coupling between CBFM-PETCO2 was lower for PS than for NPS. DISCUSSION: Perturbations to baro- and chemo-reflexes led to changes in nonlinear phase coupling that were altered in presyncope. Although physiological interpretation of changes in phase coupling are less than clear at this time, our results show that such nonlinear indexes may provide a helpful perspective in understanding the complex phenomenon of orthostatically mediated syncope.

Transfer function analysis of gender-related differences in cerebral autoregulation.

Effects of gender in cardiovascular regulation are widely investigated, however differences in cerebral autoregulation (CA) between genders remains less explored. In the present study, we used spectral analysis to analyze differences in cerebral autoregulation between 10 men and 10 age-matched women. Subjects rested in a supine position (20 min) and then were passively tilted to a 70-degree head up tilt position (30 min). During the first 10 min of supine they breathed only room air (Supine Control) while during the second 10 min of supine they breathed room air or room air plus 5% CO2 in a Pseudo Random Binary Sequence (PRBS) (Supine PRBS). During the first 10 min of tilt, subjects breathed room air or room air plus 5% CO2 switched in a PRBS (Tilt PRBS). For the remaining 20 min of tilt, they breathed only room air (Tilt Control). Blood pressure (BP) and cerebral blood flow velocity (CBFV) were non-invasively recorded using Finapres and Transcranial Doppler. Coherence and transfer function between mean BP and mean CBFV were estimated. During Supine Control, women had higher coherence (p < 0.05) and transfer function gain (p < 0.01) within 0.03-0.10 Hz and 0.22-0.31 Hz than men. During tilt, coherence within 0.05-0.26 Hz were higher in men than in women (P < 0.02). Although the reasons for these gender-related differences in cerebral autoregulation remain unclear, our results suggest that in investigating cerebral autoregulation, gender may need to be considered as a factor.

Orthostatic modification of ventilatory dynamic response to carbon dioxide perturbations.

In order to determine whether changes in ventilatory control contribute to the observed decrease in arterial partial pressure of carbon dioxide (PaCO(2)) during head up tilt, we assessed ventilatory dynamic sensitivity to changes in PaCO(2) during supine and 70 degrees passive head up tilt. In 24 adult normals, we stimulated the ventilatory control system by switching inspired CO(2) between room air and room air+5% CO(2) in a pseudo random binary sequence. A Box-Jenkins model was used to compute ventilatory response to CO(2). Airflow, CO(2), non-invasive beat by beat blood pressure, ECG and cerebral blood flow velocity (Doppler) were recorded. During tilt, sensitivity of the ventilatory controller to CO(2) disturbance increased (from 0.45 to 0.72 L/min/mm Hg, p<0.005); minute ventilation increased (7.63 to 8.47 L/min, p<0.01), end tidal CO(2) (ETCO(2)), cerebral blood flow velocity (CBF) and baroreflex sensitivity decreased (46.9 to 42.9 mm Hg, p<0.001; 84.9 to 72.9 cm/s, p<0.001; and 17.6 to 5.5 ms/mm Hg, p<0.001). The primary observation from our study was that the sensitivity of ventilatory control system to perturbations in ETCO(2) increased during tilt. Taken together with decrease in mean levels of ETCO(2) and an increase in minute ventilation, these results suggest that during tilt, a change in the regulated level or 'set point' of PaCO(2) may occur.