Hello Welcome to HCM. Since you have not mentioned your symptoms here I presume you are having no symptoms. The eidnce of prominent vascular markings bilaterally and tubular heart pint towards emphysema which is a disease of the lungs caused due to air trapping and airway obstruction . It is found in chronic smokers. You have not mentioned any history of smoking. If you had been smoking this could very well be emohysema. If you have never smoked then this could be a normal variant or some associated disease of the lung. I would have to look at the chest x ray to comment more. I recommend you a HRCT of the chest to be evaluated further for the findings of the chest x ray. It will provide a clear picture of your lung abnormalities if any. Please do the HRCT chest and revert back worth reports and your detailed history about symptoms and smoking. Wishing you good health. Regards