G. R. No. 179177 18 of 29 http://sc.judiciary.gov.ph/jurisprudence/2009/july2009/179177.htm contracted under working conditions that involve any of the following risks a) If the heart disease was known to have been present during employment, there must be proof that an acute exacerbation was clearly precipitated by the unusual strain by reasons of the nature of his work. b) The strain of the work that brings about an acute attack must be sufficient severity and must be followed within 24 hours by the clinical signs of cardiac insult to constitute causal relationship. c) If a person who was apparently asymptomatic before being subjected to strain at work showed signs and symptoms of cardiac injury during the performance of his work and such symptoms and signs persisted, it is reasonable to claim a causal relationship. Consequently, for Cardio-Vascular Disease to constitute an occupational disease for which the seafarer may claim compensation, it is incumbent upon said seafarer to show that he developed the same under any of the three conditions identified above. In the present case, petitioner Nisda was diagnosed to be suffering from a CardioVascular Disease, specifically, a Coronary Artery Disease, only shortly after disembarking from M/V Algosaibi-42 and arriving in the Philippines. Petitioner Nisdas disease was serious enough to necessitate a Triple Bypass Operation on his heart. Petitioner Nisdas Coronary Artery Disease was diagnosed only after numerous tests and evaluations conducted, owing to his consistent and persistent physical complaints. His medical history was well-documented. On 5 May 2002, petitioner Nisda was brought to the Dar Al-Taafi Medical Services, a clinic in Saudi Arabia, for pain of parascapular region of [64] 6 months duration [with] paresthesia and numbness of both upper limbs. Petitioner Nisda then had blood pressure of 160/100 mm/Hg. Dr. Hossam A. Abubeih, an Orthopedist at the clinic, initially diagnosed petitioner Nisda as having Myositis of the parascapular region with paresthesia on the upper limbs. On 19 July 2002, only two days after being repatriated to the Philippines, Dr. Torrefiel attended to petitioner Nisda in Iloilo when the latter suffered from chest pain which radiates to the back associated with exertional [65] dyspnea. Dr. Torrefiel advised petitioner Nisda to undergo complete cardiac evaluation. In view of Dr. Torrefiels advice, St. Magdalene Diagnostic Clinic, Inc., the accredited health service provider of respondent Nobel, conducted on 22 July 2002 an ECG/EKG of petitioner Nisdas heart, revealing that the left ventricle thereof was 1/28/2016 1:07 PM